diff --git a/Dockerfile b/Dockerfile
index c41520df32..0e984a1640 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -24,6 +24,7 @@ COPY packages/adapter-utils/package.json packages/adapter-utils/
 COPY packages/google-sheets-mcp-server/package.json packages/google-sheets-mcp-server/
 COPY packages/kv-demo-mcp-server/package.json packages/kv-demo-mcp-server/
 COPY packages/mcp-server/package.json packages/mcp-server/
+COPY packages/paperclip-runner/package.json packages/paperclip-runner/
 COPY packages/skills-catalog/package.json packages/skills-catalog/
 COPY packages/tailscale-https-broker/package.json packages/tailscale-https-broker/
 COPY packages/teams-catalog/package.json packages/teams-catalog/
diff --git a/packages/paperclip-runner/README.md b/packages/paperclip-runner/README.md
new file mode 100644
index 0000000000..efb874ce07
--- /dev/null
+++ b/packages/paperclip-runner/README.md
@@ -0,0 +1,27 @@
+# Paperclip Runner
+
+This private workspace package contains the staged Paperclip Runner work.
+
+This change adds only the language-neutral PRP v1 contract. It does not add a
+runtime, a server adapter, or a public package export. The schemas and fixtures
+are safe to review and merge before production behavior exists.
+
+The first provider scope is Codex. The protocol contains provider-neutral event
+and semantic receipt shapes, but their presence does not authorize a tool or
+enable a provider.
+
+Run the protocol gate with:
+
+```sh
+pnpm --filter @paperclipai/paperclip-runner check:protocol
+```
+
+Use `generate:protocol-manifest` after a schema or fixture change. Commit the
+updated manifest with its source change. Do not edit the manifest by hand.
+The gate compiles every schema with AJV 2020-12. It validates accepted replay,
+question, and cross-language conformance fixtures against the declared schemas.
+It also proves that the unsupported required-version fixture is rejected.
+
+The next pull request will add TypeScript validation and replay behavior. The
+public root and `./testing` exports will arrive with the package boundary pull
+request.
diff --git a/packages/paperclip-runner/package.json b/packages/paperclip-runner/package.json
new file mode 100644
index 0000000000..c289744ee4
--- /dev/null
+++ b/packages/paperclip-runner/package.json
@@ -0,0 +1,21 @@
+{
+  "name": "@paperclipai/paperclip-runner",
+  "version": "0.0.0",
+  "private": true,
+  "license": "MIT",
+  "engines": {
+    "node": ">=24.11.0"
+  },
+  "type": "module",
+  "scripts": {
+    "build": "pnpm run check:protocol-manifest",
+    "typecheck": "node --check scripts/protocol-contract.mjs && node --check scripts/generate-protocol-manifest.mjs",
+    "test": "node --test test/protocol-contract.test.mjs",
+    "generate:protocol-manifest": "node scripts/generate-protocol-manifest.mjs",
+    "check:protocol-manifest": "node scripts/generate-protocol-manifest.mjs --check",
+    "check:protocol": "pnpm run typecheck && pnpm run check:protocol-manifest && pnpm test"
+  },
+  "devDependencies": {
+    "ajv": "^8.20.0"
+  }
+}
diff --git a/packages/paperclip-runner/protocol/README.md b/packages/paperclip-runner/protocol/README.md
new file mode 100644
index 0000000000..405c2bbd34
--- /dev/null
+++ b/packages/paperclip-runner/protocol/README.md
@@ -0,0 +1,32 @@
+# PRP v1 Contract
+
+The JSON Schema files in `schemas/` are the language-neutral source of truth for
+Paperclip Runner Protocol version 1. The fixtures in `fixtures/` define accepted
+and rejected compatibility cases.
+
+## Compatibility
+
+- `protocolVersion`, `fixtureVersion`, and `event.schemaVersion` are required.
+- A consumer fails closed when a required version or schema discriminator is
+  not supported.
+- A v1 envelope can contain an unknown optional property when its schema marks
+  that object as extensible.
+- A consumer ignores an unknown optional property until a later contract gives
+  it meaning.
+- A required field, enum value, or typed structured-input field is not optional.
+- Question and answer identifiers are stable across the provider boundary.
+
+The `unknown-optional-fields.json` fixture must be accepted. The
+`unsupported-required-version.json` fixture must be rejected.
+
+## Scope
+
+The first provider descriptor and adapter fixture cover Codex only. The schemas
+for provider-neutral events and semantic receipts do not enable those actions.
+Discovery and authorization are separate contracts.
+
+The conformance manifest records every source file and its SHA-256 digest. Run
+`pnpm generate:protocol-manifest` from this package after a source change. CI
+runs the same generator with `--check` to reject drift. This check also compiles
+the JSON Schemas and validates every replay, question, and cross-language
+conformance fixture against its declared schema.
diff --git a/packages/paperclip-runner/protocol/fixtures/conformance-expected-output.json b/packages/paperclip-runner/protocol/fixtures/conformance-expected-output.json
new file mode 100644
index 0000000000..6dc9bc9aff
--- /dev/null
+++ b/packages/paperclip-runner/protocol/fixtures/conformance-expected-output.json
@@ -0,0 +1 @@
+{"schemaVersion":"paperclip.runner.conformance.output.v1","runIdentity":{"runId":"run_conformance_0001","sessionId":"session_conformance_0001"},"result":{"status":"succeeded","summary":"Standalone Conformance fixture accepted."}}
diff --git a/packages/paperclip-runner/protocol/fixtures/conformance-minimal-run.json b/packages/paperclip-runner/protocol/fixtures/conformance-minimal-run.json
new file mode 100644
index 0000000000..ad6a9fc579
--- /dev/null
+++ b/packages/paperclip-runner/protocol/fixtures/conformance-minimal-run.json
@@ -0,0 +1,29 @@
+{
+  "schemaVersion": "paperclip.runner.conformance.fixture.v1",
+  "run": {
+    "runId": "run_conformance_0001",
+    "sessionId": "session_conformance_0001",
+    "companyId": "company_conformance",
+    "issueId": "issue_conformance",
+    "agentId": "agent_conformance"
+  },
+  "events": [
+    {
+      "eventId": "event_conformance_0001",
+      "runId": "run_conformance_0001",
+      "sequence": 1,
+      "type": "run.started"
+    },
+    {
+      "eventId": "event_conformance_0002",
+      "runId": "run_conformance_0001",
+      "sequence": 2,
+      "type": "run.completed"
+    }
+  ],
+  "result": {
+    "runId": "run_conformance_0001",
+    "status": "succeeded",
+    "summary": "Standalone Conformance fixture accepted."
+  }
+}
diff --git a/packages/paperclip-runner/protocol/fixtures/questions/codex.json b/packages/paperclip-runner/protocol/fixtures/questions/codex.json
new file mode 100644
index 0000000000..d1ec06850f
--- /dev/null
+++ b/packages/paperclip-runner/protocol/fixtures/questions/codex.json
@@ -0,0 +1,40 @@
+{
+  "schema": "paperclip.question_adapter_fixture.v1",
+  "adapter": "codex",
+  "nativeRequest": {
+    "method": "item/tool/requestUserInput",
+    "params": {
+      "title": "Deployment input",
+      "questions": [{
+        "id": "environment",
+        "header": "Environment",
+        "question": "Where should we deploy?",
+        "options": [
+          { "label": "Staging", "description": "Deploy to staging first." },
+          { "label": "Production", "description": "Deploy directly to production." }
+        ]
+      }]
+    }
+  },
+  "canonicalQuestionSet": {
+    "schema": "paperclip.question_set.v1",
+    "title": "Deployment input",
+    "submitLabel": "Submit answers",
+    "questions": [{
+      "id": "environment",
+      "header": "Environment",
+      "prompt": "Where should we deploy?",
+      "required": true,
+      "answerMode": "single_select",
+      "options": [
+        { "id": "option-1", "label": "Staging", "description": "Deploy to staging first." },
+        { "id": "option-2", "label": "Production", "description": "Deploy directly to production." }
+      ]
+    }]
+  },
+  "canonicalResponse": {
+    "schema": "paperclip.question_response.v1",
+    "answers": { "environment": { "selectedOptionIds": ["option-1"] } }
+  },
+  "nativeResponse": { "answers": { "environment": { "answers": ["Staging"] } } }
+}
diff --git a/packages/paperclip-runner/protocol/fixtures/replay/duplicate-event.json b/packages/paperclip-runner/protocol/fixtures/replay/duplicate-event.json
new file mode 100644
index 0000000000..4555eb448a
--- /dev/null
+++ b/packages/paperclip-runner/protocol/fixtures/replay/duplicate-event.json
@@ -0,0 +1,30 @@
+{
+  "schema": "paperclip.prp.fixture.v1", "fixtureVersion": 1, "protocolVersion": 1,
+  "name": "Duplicate event", "description": "At-least-once delivery repeats one source event without repeating its effect.",
+  "identity": {
+    "schema": "paperclip.prp.identity.v1", "companyId": "company_replay", "issueId": "issue_replay_duplicate",
+    "runId": "run_replay_duplicate", "environmentLeaseId": "lease_replay_duplicate", "runnerInstanceId": "runner_replay",
+    "normalizedSessionId": "session_replay_duplicate", "driverSessionId": "driver_replay_duplicate"
+  },
+  "capabilities": {
+    "schema": "paperclip.prp.capabilities.v1", "sessionReusePolicy": "new_per_run", "driver": { "kind": "fake", "version": "1.0.0" },
+    "steer": false, "interrupt": true, "resume": true, "runtimeRequests": false, "structuredResult": true, "typedEvents": true
+  },
+  "commands": [
+    { "schema": "paperclip.prp.command.v1", "commandId": "command_duplicate_prepare", "controllerSeq": 1, "type": "run.prepare", "issuedAt": "2026-08-07T12:30:00.000Z", "payload": {} }
+  ],
+  "events": [
+    { "schema": "paperclip.prp.event.v1", "sourceEventId": "event_duplicate_01", "sourceSeq": 1, "sourceInstanceId": "runner_replay", "sourceKind": "runner", "runId": "run_replay_duplicate", "normalizedSessionId": "session_replay_duplicate", "eventType": "session.started", "schemaVersion": 1, "priority": 0, "emittedAt": "2026-08-07T12:30:00.010Z", "payload": {} },
+    { "schema": "paperclip.prp.event.v1", "sourceEventId": "event_duplicate_02", "sourceSeq": 2, "sourceInstanceId": "runner_replay", "sourceKind": "runner", "runId": "run_replay_duplicate", "normalizedSessionId": "session_replay_duplicate", "turnId": "turn_replay_duplicate", "eventType": "turn.started", "schemaVersion": 1, "priority": 1, "emittedAt": "2026-08-07T12:30:00.020Z", "payload": {} },
+    { "schema": "paperclip.prp.event.v1", "sourceEventId": "event_duplicate_03", "sourceSeq": 3, "sourceInstanceId": "runner_replay", "sourceKind": "runner", "runId": "run_replay_duplicate", "normalizedSessionId": "session_replay_duplicate", "turnId": "turn_replay_duplicate", "itemId": "item_replay_duplicate", "eventType": "item.completed", "schemaVersion": 1, "priority": 1, "emittedAt": "2026-08-07T12:30:00.030Z", "payload": { "kind": "assistant_message", "text": "Exactly one projection." } },
+    { "schema": "paperclip.prp.event.v1", "sourceEventId": "event_duplicate_03", "sourceSeq": 3, "sourceInstanceId": "runner_replay", "sourceKind": "runner", "runId": "run_replay_duplicate", "normalizedSessionId": "session_replay_duplicate", "turnId": "turn_replay_duplicate", "itemId": "item_replay_duplicate", "eventType": "item.completed", "schemaVersion": 1, "priority": 1, "emittedAt": "2026-08-07T12:30:00.030Z", "payload": { "kind": "assistant_message", "text": "Exactly one projection." } },
+    {
+      "schema": "paperclip.prp.event.v1", "sourceEventId": "event_duplicate_04", "sourceSeq": 4, "sourceInstanceId": "runner_replay", "sourceKind": "runner", "runId": "run_replay_duplicate", "normalizedSessionId": "session_replay_duplicate", "eventType": "run.result.proposed", "schemaVersion": 1, "priority": 0, "emittedAt": "2026-08-07T12:30:00.040Z",
+      "payload": { "schema": "paperclip.run_result.v1", "reportedWorkDisposition": "done", "summary": "Duplicate delivery was idempotent.", "completionClaim": { "contractRevision": "replay-contract-v1", "objectiveSatisfied": true, "criteria": [], "remainingWork": [] }, "evidence": [], "verification": [], "attentionRequests": [], "artifacts": [] }
+    },
+    { "schema": "paperclip.prp.event.v1", "sourceEventId": "event_duplicate_05", "sourceSeq": 5, "sourceInstanceId": "runner_replay", "sourceKind": "runner", "runId": "run_replay_duplicate", "normalizedSessionId": "session_replay_duplicate", "turnId": "turn_replay_duplicate", "eventType": "turn.completed", "schemaVersion": 1, "priority": 0, "emittedAt": "2026-08-07T12:30:00.050Z", "payload": {} },
+    { "schema": "paperclip.prp.event.v1", "sourceEventId": "event_duplicate_06", "sourceSeq": 6, "sourceInstanceId": "runner_replay", "sourceKind": "runner", "runId": "run_replay_duplicate", "normalizedSessionId": "session_replay_duplicate", "eventType": "run.terminal", "schemaVersion": 1, "priority": 0, "emittedAt": "2026-08-07T12:30:00.060Z", "payload": { "schema": "paperclip.prp.terminal.v1", "turnTerminalState": "completed", "runTerminalState": "succeeded", "reportedWorkDisposition": "done" } }
+  ],
+  "requests": [],
+  "result": { "schema": "paperclip.run_result.v1", "reportedWorkDisposition": "done", "summary": "Duplicate delivery was idempotent.", "completionClaim": { "contractRevision": "replay-contract-v1", "objectiveSatisfied": true, "criteria": [], "remainingWork": [] }, "evidence": [], "verification": [], "attentionRequests": [], "artifacts": [] }
+}
diff --git a/packages/paperclip-runner/protocol/fixtures/replay/failed-run.json b/packages/paperclip-runner/protocol/fixtures/replay/failed-run.json
new file mode 100644
index 0000000000..8327cd5f5d
--- /dev/null
+++ b/packages/paperclip-runner/protocol/fixtures/replay/failed-run.json
@@ -0,0 +1,106 @@
+{
+  "schema": "paperclip.prp.fixture.v1",
+  "fixtureVersion": 1,
+  "protocolVersion": 1,
+  "name": "Failed run",
+  "description": "The driver reports an item and turn failure before the run terminalizes.",
+  "identity": {
+    "schema": "paperclip.prp.identity.v1",
+    "companyId": "company_replay",
+    "issueId": "issue_replay_failed",
+    "runId": "run_replay_failed",
+    "environmentLeaseId": "lease_replay_failed",
+    "runnerInstanceId": "runner_replay",
+    "normalizedSessionId": "session_replay_failed",
+    "driverSessionId": "driver_replay_failed"
+  },
+  "capabilities": {
+    "schema": "paperclip.prp.capabilities.v1",
+    "sessionReusePolicy": "new_per_run",
+    "driver": { "kind": "fake", "version": "1.0.0" },
+    "steer": true,
+    "interrupt": true,
+    "resume": true,
+    "runtimeRequests": true,
+    "structuredResult": true,
+    "typedEvents": true
+  },
+  "commands": [
+    {
+      "schema": "paperclip.prp.command.v1",
+      "commandId": "command_failed_prepare",
+      "controllerSeq": 1,
+      "type": "run.prepare",
+      "issuedAt": "2026-08-07T12:10:00.000Z",
+      "payload": {}
+    },
+    {
+      "schema": "paperclip.prp.command.v1",
+      "commandId": "command_failed_turn",
+      "controllerSeq": 2,
+      "type": "turn.start",
+      "issuedAt": "2026-08-07T12:10:00.010Z",
+      "payload": { "text": "Run failing scenario" }
+    }
+  ],
+  "events": [
+    {
+      "schema": "paperclip.prp.event.v1", "sourceEventId": "event_failed_01", "sourceSeq": 1,
+      "sourceInstanceId": "runner_replay", "sourceKind": "runner", "runId": "run_replay_failed",
+      "normalizedSessionId": "session_replay_failed", "eventType": "session.started", "schemaVersion": 1,
+      "priority": 0, "emittedAt": "2026-08-07T12:10:00.020Z", "payload": {}
+    },
+    {
+      "schema": "paperclip.prp.event.v1", "sourceEventId": "event_failed_02", "sourceSeq": 2,
+      "sourceInstanceId": "runner_replay", "sourceKind": "runner", "runId": "run_replay_failed",
+      "normalizedSessionId": "session_replay_failed", "turnId": "turn_replay_failed",
+      "eventType": "turn.started", "schemaVersion": 1, "priority": 1,
+      "emittedAt": "2026-08-07T12:10:00.030Z", "payload": {}
+    },
+    {
+      "schema": "paperclip.prp.event.v1", "sourceEventId": "event_failed_03", "sourceSeq": 3,
+      "sourceInstanceId": "runner_replay", "sourceKind": "runner", "runId": "run_replay_failed",
+      "normalizedSessionId": "session_replay_failed", "turnId": "turn_replay_failed", "itemId": "item_failed_command",
+      "eventType": "item.failed", "schemaVersion": 1, "priority": 0,
+      "emittedAt": "2026-08-07T12:10:00.040Z", "payload": { "kind": "command", "message": "Command exited with code 1" }
+    },
+    {
+      "schema": "paperclip.prp.event.v1", "sourceEventId": "event_failed_04", "sourceSeq": 4,
+      "sourceInstanceId": "runner_replay", "sourceKind": "runner", "runId": "run_replay_failed",
+      "normalizedSessionId": "session_replay_failed", "turnId": "turn_replay_failed",
+      "eventType": "run.result.proposed", "schemaVersion": 1, "priority": 0,
+      "emittedAt": "2026-08-07T12:10:00.050Z",
+      "payload": {
+        "schema": "paperclip.run_result.v1", "reportedWorkDisposition": "yielded",
+        "summary": "The scripted command failed and needs a retry.",
+        "completionClaim": { "contractRevision": "replay-contract-v1", "objectiveSatisfied": false, "criteria": [], "remainingWork": [{ "description": "Retry the failed command", "blocksCompletion": true }] },
+        "evidence": [], "verification": [{ "commandOrCheck": "fake command", "status": "failed" }],
+        "attentionRequests": [], "artifacts": [],
+        "continuation": { "kind": "retry", "summary": "Retry after correcting the command", "idempotencyKey": "retry_replay_failed" }
+      }
+    },
+    {
+      "schema": "paperclip.prp.event.v1", "sourceEventId": "event_failed_05", "sourceSeq": 5,
+      "sourceInstanceId": "runner_replay", "sourceKind": "runner", "runId": "run_replay_failed",
+      "normalizedSessionId": "session_replay_failed", "turnId": "turn_replay_failed",
+      "eventType": "turn.failed", "schemaVersion": 1, "priority": 0,
+      "emittedAt": "2026-08-07T12:10:00.060Z", "payload": { "message": "Fake driver failure" }
+    },
+    {
+      "schema": "paperclip.prp.event.v1", "sourceEventId": "event_failed_06", "sourceSeq": 6,
+      "sourceInstanceId": "runner_replay", "sourceKind": "runner", "runId": "run_replay_failed",
+      "normalizedSessionId": "session_replay_failed", "eventType": "run.terminal", "schemaVersion": 1,
+      "priority": 0, "emittedAt": "2026-08-07T12:10:00.070Z",
+      "payload": { "schema": "paperclip.prp.terminal.v1", "turnTerminalState": "failed", "runTerminalState": "failed", "reportedWorkDisposition": "yielded" }
+    }
+  ],
+  "requests": [],
+  "result": {
+    "schema": "paperclip.run_result.v1", "reportedWorkDisposition": "yielded",
+    "summary": "The scripted command failed and needs a retry.",
+    "completionClaim": { "contractRevision": "replay-contract-v1", "objectiveSatisfied": false, "criteria": [], "remainingWork": [{ "description": "Retry the failed command", "blocksCompletion": true }] },
+    "evidence": [], "verification": [{ "commandOrCheck": "fake command", "status": "failed" }],
+    "attentionRequests": [], "artifacts": [],
+    "continuation": { "kind": "retry", "summary": "Retry after correcting the command", "idempotencyKey": "retry_replay_failed" }
+  }
+}
diff --git a/packages/paperclip-runner/protocol/fixtures/replay/happy-path.json b/packages/paperclip-runner/protocol/fixtures/replay/happy-path.json
new file mode 100644
index 0000000000..c5f656d22e
--- /dev/null
+++ b/packages/paperclip-runner/protocol/fixtures/replay/happy-path.json
@@ -0,0 +1,230 @@
+{
+  "schema": "paperclip.prp.fixture.v1",
+  "fixtureVersion": 1,
+  "protocolVersion": 1,
+  "name": "Happy path",
+  "description": "A typed assistant message completes and the run proposes a successful result.",
+  "identity": {
+    "schema": "paperclip.prp.identity.v1",
+    "companyId": "company_replay",
+    "issueId": "issue_replay_happy",
+    "runId": "run_replay_happy",
+    "environmentLeaseId": "lease_replay_happy",
+    "runnerInstanceId": "runner_replay",
+    "normalizedSessionId": "session_replay_happy",
+    "driverSessionId": "driver_replay_happy",
+    "providerSessionId": "provider_replay_happy"
+  },
+  "capabilities": {
+    "schema": "paperclip.prp.capabilities.v1",
+    "sessionReusePolicy": "new_per_run",
+    "driver": { "kind": "fake", "version": "1.0.0" },
+    "steer": true,
+    "interrupt": true,
+    "resume": true,
+    "runtimeRequests": true,
+    "structuredResult": true,
+    "typedEvents": true,
+    "unsupported": []
+  },
+  "commands": [
+    {
+      "schema": "paperclip.prp.command.v1",
+      "commandId": "command_happy_prepare",
+      "controllerSeq": 1,
+      "type": "run.prepare",
+      "issuedAt": "2026-08-07T12:00:00.000Z",
+      "payload": { "workspace": "fixture" }
+    },
+    {
+      "schema": "paperclip.prp.command.v1",
+      "commandId": "command_happy_session",
+      "controllerSeq": 2,
+      "type": "session.open",
+      "issuedAt": "2026-08-07T12:00:00.010Z",
+      "payload": { "reuse": "new_per_run" }
+    },
+    {
+      "schema": "paperclip.prp.command.v1",
+      "commandId": "command_happy_turn",
+      "controllerSeq": 3,
+      "type": "turn.start",
+      "issuedAt": "2026-08-07T12:00:00.020Z",
+      "payload": { "text": "Inspect the fixture" }
+    }
+  ],
+  "events": [
+    {
+      "schema": "paperclip.prp.event.v1",
+      "sourceEventId": "event_happy_01",
+      "sourceSeq": 1,
+      "sourceInstanceId": "runner_replay",
+      "sourceKind": "runner",
+      "runId": "run_replay_happy",
+      "normalizedSessionId": "session_replay_happy",
+      "eventType": "runtime.phase.changed",
+      "schemaVersion": 1,
+      "priority": 1,
+      "emittedAt": "2026-08-07T12:00:00.030Z",
+      "payload": { "phase": "workspace_preparing" }
+    },
+    {
+      "schema": "paperclip.prp.event.v1",
+      "sourceEventId": "event_happy_02",
+      "sourceSeq": 2,
+      "sourceInstanceId": "runner_replay",
+      "sourceKind": "runner",
+      "runId": "run_replay_happy",
+      "normalizedSessionId": "session_replay_happy",
+      "eventType": "session.started",
+      "schemaVersion": 1,
+      "priority": 0,
+      "emittedAt": "2026-08-07T12:00:00.040Z",
+      "payload": { "driverSessionId": "driver_replay_happy" }
+    },
+    {
+      "schema": "paperclip.prp.event.v1",
+      "sourceEventId": "event_happy_03",
+      "sourceSeq": 3,
+      "sourceInstanceId": "runner_replay",
+      "sourceKind": "runner",
+      "runId": "run_replay_happy",
+      "normalizedSessionId": "session_replay_happy",
+      "turnId": "turn_replay_happy",
+      "eventType": "turn.started",
+      "schemaVersion": 1,
+      "priority": 1,
+      "emittedAt": "2026-08-07T12:00:00.050Z",
+      "payload": {}
+    },
+    {
+      "schema": "paperclip.prp.event.v1",
+      "sourceEventId": "event_happy_04",
+      "sourceSeq": 4,
+      "sourceInstanceId": "runner_replay",
+      "sourceKind": "runner",
+      "runId": "run_replay_happy",
+      "normalizedSessionId": "session_replay_happy",
+      "turnId": "turn_replay_happy",
+      "itemId": "item_replay_message",
+      "eventType": "item.started",
+      "schemaVersion": 1,
+      "priority": 1,
+      "emittedAt": "2026-08-07T12:00:00.060Z",
+      "payload": { "kind": "assistant_message", "text": "" }
+    },
+    {
+      "schema": "paperclip.prp.event.v1",
+      "sourceEventId": "event_happy_05",
+      "sourceSeq": 5,
+      "sourceInstanceId": "runner_replay",
+      "sourceKind": "runner",
+      "runId": "run_replay_happy",
+      "normalizedSessionId": "session_replay_happy",
+      "turnId": "turn_replay_happy",
+      "itemId": "item_replay_message",
+      "eventType": "item.delta",
+      "schemaVersion": 1,
+      "priority": 2,
+      "emittedAt": "2026-08-07T12:00:00.070Z",
+      "payload": { "text": "Validated fixture. " }
+    },
+    {
+      "schema": "paperclip.prp.event.v1",
+      "sourceEventId": "event_happy_06",
+      "sourceSeq": 6,
+      "sourceInstanceId": "runner_replay",
+      "sourceKind": "runner",
+      "runId": "run_replay_happy",
+      "normalizedSessionId": "session_replay_happy",
+      "turnId": "turn_replay_happy",
+      "itemId": "item_replay_message",
+      "eventType": "item.completed",
+      "schemaVersion": 1,
+      "priority": 1,
+      "emittedAt": "2026-08-07T12:00:00.080Z",
+      "payload": { "kind": "assistant_message", "text": "Validated fixture. Replay complete." }
+    },
+    {
+      "schema": "paperclip.prp.event.v1",
+      "sourceEventId": "event_happy_07",
+      "sourceSeq": 7,
+      "sourceInstanceId": "runner_replay",
+      "sourceKind": "runner",
+      "runId": "run_replay_happy",
+      "normalizedSessionId": "session_replay_happy",
+      "turnId": "turn_replay_happy",
+      "eventType": "run.result.proposed",
+      "schemaVersion": 1,
+      "priority": 0,
+      "emittedAt": "2026-08-07T12:00:00.090Z",
+      "payload": {
+        "schema": "paperclip.run_result.v1",
+        "reportedWorkDisposition": "done",
+        "summary": "The scripted run completed successfully.",
+        "completionClaim": {
+          "contractRevision": "replay-contract-v1",
+          "objectiveSatisfied": true,
+          "criteria": [],
+          "remainingWork": []
+        },
+        "evidence": [],
+        "verification": [{ "commandOrCheck": "fixture replay", "status": "passed" }],
+        "attentionRequests": [],
+        "artifacts": []
+      }
+    },
+    {
+      "schema": "paperclip.prp.event.v1",
+      "sourceEventId": "event_happy_08",
+      "sourceSeq": 8,
+      "sourceInstanceId": "runner_replay",
+      "sourceKind": "runner",
+      "runId": "run_replay_happy",
+      "normalizedSessionId": "session_replay_happy",
+      "turnId": "turn_replay_happy",
+      "eventType": "turn.completed",
+      "schemaVersion": 1,
+      "priority": 0,
+      "emittedAt": "2026-08-07T12:00:00.100Z",
+      "payload": {}
+    },
+    {
+      "schema": "paperclip.prp.event.v1",
+      "sourceEventId": "event_happy_09",
+      "sourceSeq": 9,
+      "sourceInstanceId": "runner_replay",
+      "sourceKind": "runner",
+      "runId": "run_replay_happy",
+      "normalizedSessionId": "session_replay_happy",
+      "eventType": "run.terminal",
+      "schemaVersion": 1,
+      "priority": 0,
+      "emittedAt": "2026-08-07T12:00:00.110Z",
+      "payload": {
+        "schema": "paperclip.prp.terminal.v1",
+        "turnTerminalState": "completed",
+        "runTerminalState": "succeeded",
+        "reportedWorkDisposition": "done",
+        "workAssessmentId": "assessment_replay_happy",
+        "statusDecisionId": "decision_replay_happy"
+      }
+    }
+  ],
+  "requests": [],
+  "result": {
+    "schema": "paperclip.run_result.v1",
+    "reportedWorkDisposition": "done",
+    "summary": "The scripted run completed successfully.",
+    "completionClaim": {
+      "contractRevision": "replay-contract-v1",
+      "objectiveSatisfied": true,
+      "criteria": [],
+      "remainingWork": []
+    },
+    "evidence": [],
+    "verification": [{ "commandOrCheck": "fixture replay", "status": "passed" }],
+    "attentionRequests": [],
+    "artifacts": []
+  }
+}
diff --git a/packages/paperclip-runner/protocol/fixtures/replay/interrupted-run.json b/packages/paperclip-runner/protocol/fixtures/replay/interrupted-run.json
new file mode 100644
index 0000000000..26bf4ed3aa
--- /dev/null
+++ b/packages/paperclip-runner/protocol/fixtures/replay/interrupted-run.json
@@ -0,0 +1,90 @@
+{
+  "schema": "paperclip.prp.fixture.v1",
+  "fixtureVersion": 1,
+  "protocolVersion": 1,
+  "name": "Interrupted run",
+  "description": "A pending runtime permission request is followed by an explicit turn interruption.",
+  "identity": {
+    "schema": "paperclip.prp.identity.v1", "companyId": "company_replay", "issueId": "issue_replay_interrupted",
+    "runId": "run_replay_interrupted", "environmentLeaseId": "lease_replay_interrupted",
+    "runnerInstanceId": "runner_replay", "normalizedSessionId": "session_replay_interrupted",
+    "driverSessionId": "driver_replay_interrupted"
+  },
+  "capabilities": {
+    "schema": "paperclip.prp.capabilities.v1", "sessionReusePolicy": "reuse_per_issue",
+    "driver": { "kind": "fake", "version": "1.0.0" }, "steer": true, "interrupt": true,
+    "resume": true, "runtimeRequests": true, "structuredResult": true, "typedEvents": true
+  },
+  "commands": [
+    {
+      "schema": "paperclip.prp.command.v1", "commandId": "command_interrupted_prepare", "controllerSeq": 1,
+      "type": "run.prepare", "issuedAt": "2026-08-07T12:20:00.000Z", "payload": {}
+    },
+    {
+      "schema": "paperclip.prp.command.v1", "commandId": "command_interrupted_turn", "controllerSeq": 2,
+      "type": "turn.start", "issuedAt": "2026-08-07T12:20:00.010Z", "payload": { "text": "Wait for interruption" }
+    },
+    {
+      "schema": "paperclip.prp.command.v1", "commandId": "command_interrupted_interrupt", "controllerSeq": 3,
+      "type": "turn.interrupt", "issuedAt": "2026-08-07T12:20:00.050Z", "payload": { "reason": "operator" }
+    }
+  ],
+  "events": [
+    {
+      "schema": "paperclip.prp.event.v1", "sourceEventId": "event_interrupted_01", "sourceSeq": 1,
+      "sourceInstanceId": "runner_replay", "sourceKind": "runner", "runId": "run_replay_interrupted",
+      "normalizedSessionId": "session_replay_interrupted", "eventType": "session.started", "schemaVersion": 1,
+      "priority": 0, "emittedAt": "2026-08-07T12:20:00.020Z", "payload": {}
+    },
+    {
+      "schema": "paperclip.prp.event.v1", "sourceEventId": "event_interrupted_02", "sourceSeq": 2,
+      "sourceInstanceId": "runner_replay", "sourceKind": "runner", "runId": "run_replay_interrupted",
+      "normalizedSessionId": "session_replay_interrupted", "turnId": "turn_replay_interrupted",
+      "eventType": "turn.started", "schemaVersion": 1, "priority": 1,
+      "emittedAt": "2026-08-07T12:20:00.030Z", "payload": {}
+    },
+    {
+      "schema": "paperclip.prp.event.v1", "sourceEventId": "event_interrupted_03", "sourceSeq": 3,
+      "sourceInstanceId": "runner_replay", "sourceKind": "runner", "runId": "run_replay_interrupted",
+      "normalizedSessionId": "session_replay_interrupted", "turnId": "turn_replay_interrupted",
+      "eventType": "runtime_request.created", "schemaVersion": 1, "priority": 0,
+      "emittedAt": "2026-08-07T12:20:00.040Z",
+      "payload": { "request": { "schema": "paperclip.runtime_request.v1", "requestKind": "runtime", "requestId": "request_interrupted_permission", "type": "permission", "status": "pending", "prompt": "Allow the fake command?" } }
+    },
+    {
+      "schema": "paperclip.prp.event.v1", "sourceEventId": "event_interrupted_04", "sourceSeq": 4,
+      "sourceInstanceId": "runner_replay", "sourceKind": "runner", "runId": "run_replay_interrupted",
+      "normalizedSessionId": "session_replay_interrupted", "turnId": "turn_replay_interrupted",
+      "eventType": "turn.interrupted", "schemaVersion": 1, "priority": 0,
+      "emittedAt": "2026-08-07T12:20:00.060Z", "payload": { "reason": "operator" }
+    },
+    {
+      "schema": "paperclip.prp.event.v1", "sourceEventId": "event_interrupted_05", "sourceSeq": 5,
+      "sourceInstanceId": "runner_replay", "sourceKind": "runner", "runId": "run_replay_interrupted",
+      "normalizedSessionId": "session_replay_interrupted", "eventType": "run.result.proposed", "schemaVersion": 1,
+      "priority": 0, "emittedAt": "2026-08-07T12:20:00.070Z",
+      "payload": {
+        "schema": "paperclip.run_result.v1", "reportedWorkDisposition": "yielded", "summary": "The turn was interrupted.",
+        "completionClaim": { "contractRevision": "replay-contract-v1", "objectiveSatisfied": false, "criteria": [], "remainingWork": [{ "description": "Resume the interrupted turn", "blocksCompletion": true }] },
+        "evidence": [], "verification": [], "attentionRequests": [], "artifacts": [],
+        "continuation": { "kind": "same_agent", "summary": "Resume in the same normalized session", "idempotencyKey": "resume_replay_interrupted" }
+      }
+    },
+    {
+      "schema": "paperclip.prp.event.v1", "sourceEventId": "event_interrupted_06", "sourceSeq": 6,
+      "sourceInstanceId": "runner_replay", "sourceKind": "runner", "runId": "run_replay_interrupted",
+      "normalizedSessionId": "session_replay_interrupted", "eventType": "run.terminal", "schemaVersion": 1,
+      "priority": 0, "emittedAt": "2026-08-07T12:20:00.080Z",
+      "payload": { "schema": "paperclip.prp.terminal.v1", "turnTerminalState": "interrupted", "runTerminalState": "cancelled", "reportedWorkDisposition": "yielded" }
+    }
+  ],
+  "requests": [
+    { "schema": "paperclip.runtime_request.v1", "requestKind": "runtime", "requestId": "request_interrupted_permission", "type": "permission", "status": "pending", "prompt": "Allow the fake command?" }
+  ],
+  "result": {
+    "schema": "paperclip.run_result.v1", "reportedWorkDisposition": "yielded", "summary": "The turn was interrupted.",
+    "completionClaim": { "contractRevision": "replay-contract-v1", "objectiveSatisfied": false, "criteria": [], "remainingWork": [{ "description": "Resume the interrupted turn", "blocksCompletion": true }] },
+    "evidence": [], "verification": [], "attentionRequests": [], "artifacts": [],
+    "continuation": { "kind": "same_agent", "summary": "Resume in the same normalized session", "idempotencyKey": "resume_replay_interrupted" }
+  }
+}
diff --git a/packages/paperclip-runner/protocol/fixtures/replay/source-gap.json b/packages/paperclip-runner/protocol/fixtures/replay/source-gap.json
new file mode 100644
index 0000000000..130e88e22d
--- /dev/null
+++ b/packages/paperclip-runner/protocol/fixtures/replay/source-gap.json
@@ -0,0 +1,19 @@
+{
+  "schema": "paperclip.prp.fixture.v1", "fixtureVersion": 1, "protocolVersion": 1,
+  "name": "Source sequence gap", "description": "The runner stream skips source sequence 3 and replay records the missing cursor.",
+  "identity": { "schema": "paperclip.prp.identity.v1", "companyId": "company_replay", "issueId": "issue_replay_gap", "runId": "run_replay_gap", "environmentLeaseId": "lease_replay_gap", "runnerInstanceId": "runner_replay", "normalizedSessionId": "session_replay_gap", "driverSessionId": "driver_replay_gap" },
+  "capabilities": { "schema": "paperclip.prp.capabilities.v1", "sessionReusePolicy": "new_per_run", "driver": { "kind": "fake", "version": "1.0.0" }, "steer": false, "interrupt": false, "resume": true, "runtimeRequests": false, "structuredResult": true, "typedEvents": true },
+  "commands": [{ "schema": "paperclip.prp.command.v1", "commandId": "command_gap_prepare", "controllerSeq": 1, "type": "run.prepare", "issuedAt": "2026-08-07T12:40:00.000Z", "payload": {} }],
+  "events": [
+    { "schema": "paperclip.prp.event.v1", "sourceEventId": "event_gap_01", "sourceSeq": 1, "sourceInstanceId": "runner_replay", "sourceKind": "runner", "runId": "run_replay_gap", "normalizedSessionId": "session_replay_gap", "eventType": "session.started", "schemaVersion": 1, "priority": 0, "emittedAt": "2026-08-07T12:40:00.010Z", "payload": {} },
+    { "schema": "paperclip.prp.event.v1", "sourceEventId": "event_gap_02", "sourceSeq": 2, "sourceInstanceId": "runner_replay", "sourceKind": "runner", "runId": "run_replay_gap", "normalizedSessionId": "session_replay_gap", "turnId": "turn_replay_gap", "eventType": "turn.started", "schemaVersion": 1, "priority": 1, "emittedAt": "2026-08-07T12:40:00.020Z", "payload": {} },
+    {
+      "schema": "paperclip.prp.event.v1", "sourceEventId": "event_gap_04", "sourceSeq": 4, "sourceInstanceId": "runner_replay", "sourceKind": "runner", "runId": "run_replay_gap", "normalizedSessionId": "session_replay_gap", "eventType": "run.result.proposed", "schemaVersion": 1, "priority": 0, "emittedAt": "2026-08-07T12:40:00.040Z",
+      "payload": { "schema": "paperclip.run_result.v1", "reportedWorkDisposition": "needs_review", "summary": "The source gap requires reconciliation.", "completionClaim": { "contractRevision": "replay-contract-v1", "objectiveSatisfied": false, "criteria": [], "remainingWork": [{ "description": "Replay missing source event", "blocksCompletion": true }] }, "evidence": [], "verification": [], "attentionRequests": [], "artifacts": [] }
+    },
+    { "schema": "paperclip.prp.event.v1", "sourceEventId": "event_gap_05", "sourceSeq": 5, "sourceInstanceId": "runner_replay", "sourceKind": "runner", "runId": "run_replay_gap", "normalizedSessionId": "session_replay_gap", "turnId": "turn_replay_gap", "eventType": "turn.completed", "schemaVersion": 1, "priority": 0, "emittedAt": "2026-08-07T12:40:00.050Z", "payload": {} },
+    { "schema": "paperclip.prp.event.v1", "sourceEventId": "event_gap_06", "sourceSeq": 6, "sourceInstanceId": "runner_replay", "sourceKind": "runner", "runId": "run_replay_gap", "normalizedSessionId": "session_replay_gap", "eventType": "run.terminal", "schemaVersion": 1, "priority": 0, "emittedAt": "2026-08-07T12:40:00.060Z", "payload": { "schema": "paperclip.prp.terminal.v1", "turnTerminalState": "completed", "runTerminalState": "succeeded", "reportedWorkDisposition": "needs_review" } }
+  ],
+  "requests": [],
+  "result": { "schema": "paperclip.run_result.v1", "reportedWorkDisposition": "needs_review", "summary": "The source gap requires reconciliation.", "completionClaim": { "contractRevision": "replay-contract-v1", "objectiveSatisfied": false, "criteria": [], "remainingWork": [{ "description": "Replay missing source event", "blocksCompletion": true }] }, "evidence": [], "verification": [], "attentionRequests": [], "artifacts": [] }
+}
diff --git a/packages/paperclip-runner/protocol/fixtures/replay/unknown-optional-fields.json b/packages/paperclip-runner/protocol/fixtures/replay/unknown-optional-fields.json
new file mode 100644
index 0000000000..0a51d2ab44
--- /dev/null
+++ b/packages/paperclip-runner/protocol/fixtures/replay/unknown-optional-fields.json
@@ -0,0 +1,19 @@
+{
+  "schema": "paperclip.prp.fixture.v1", "fixtureVersion": 1, "protocolVersion": 1,
+  "name": "Unknown optional fields", "description": "A future producer adds optional fields that a PRP v1 consumer preserves and ignores safely.",
+  "futureFixtureHint": { "producerVersion": "1.1-preview" },
+  "identity": { "schema": "paperclip.prp.identity.v1", "companyId": "company_replay", "issueId": "issue_replay_future", "runId": "run_replay_future", "environmentLeaseId": "lease_replay_future", "runnerInstanceId": "runner_replay", "normalizedSessionId": "session_replay_future", "driverSessionId": "driver_replay_future", "futureIdentityLabel": "preserved" },
+  "capabilities": { "schema": "paperclip.prp.capabilities.v1", "sessionReusePolicy": "new_per_run", "driver": { "kind": "fake", "version": "1.1.0", "futureDriverField": true }, "steer": true, "interrupt": true, "resume": true, "runtimeRequests": true, "structuredResult": true, "typedEvents": true, "futureCapability": { "mode": "optional" } },
+  "commands": [{ "schema": "paperclip.prp.command.v1", "commandId": "command_future_prepare", "controllerSeq": 1, "type": "run.prepare", "issuedAt": "2026-08-07T12:50:00.000Z", "payload": {}, "futureDeadlineMode": "soft" }],
+  "events": [
+    { "schema": "paperclip.prp.event.v1", "sourceEventId": "event_future_01", "sourceSeq": 1, "sourceInstanceId": "runner_replay", "sourceKind": "runner", "runId": "run_replay_future", "normalizedSessionId": "session_replay_future", "eventType": "session.started", "schemaVersion": 1, "priority": 0, "emittedAt": "2026-08-07T12:50:00.010Z", "payload": { "futureSessionDetail": "ignored" }, "futureEnvelopeField": 42 },
+    {
+      "schema": "paperclip.prp.event.v1", "sourceEventId": "event_future_02", "sourceSeq": 2, "sourceInstanceId": "runner_replay", "sourceKind": "runner", "runId": "run_replay_future", "normalizedSessionId": "session_replay_future", "eventType": "run.result.proposed", "schemaVersion": 1, "priority": 0, "emittedAt": "2026-08-07T12:50:00.020Z",
+      "payload": { "schema": "paperclip.run_result.v1", "reportedWorkDisposition": "done", "summary": "Unknown optional fields did not change the v1 projection.", "completionClaim": { "contractRevision": "replay-contract-v1", "objectiveSatisfied": true, "criteria": [], "remainingWork": [] }, "evidence": [], "verification": [], "attentionRequests": [], "artifacts": [], "futureResultAnnotation": { "safe": true } }
+    },
+    { "schema": "paperclip.prp.event.v1", "sourceEventId": "event_future_03", "sourceSeq": 3, "sourceInstanceId": "runner_replay", "sourceKind": "runner", "runId": "run_replay_future", "normalizedSessionId": "session_replay_future", "turnId": "turn_replay_future", "eventType": "turn.completed", "schemaVersion": 1, "priority": 0, "emittedAt": "2026-08-07T12:50:00.030Z", "payload": {} },
+    { "schema": "paperclip.prp.event.v1", "sourceEventId": "event_future_04", "sourceSeq": 4, "sourceInstanceId": "runner_replay", "sourceKind": "runner", "runId": "run_replay_future", "normalizedSessionId": "session_replay_future", "eventType": "run.terminal", "schemaVersion": 1, "priority": 0, "emittedAt": "2026-08-07T12:50:00.040Z", "payload": { "schema": "paperclip.prp.terminal.v1", "turnTerminalState": "completed", "runTerminalState": "succeeded", "reportedWorkDisposition": "done", "futureTerminalReason": "optional" } }
+  ],
+  "requests": [],
+  "result": { "schema": "paperclip.run_result.v1", "reportedWorkDisposition": "done", "summary": "Unknown optional fields did not change the v1 projection.", "completionClaim": { "contractRevision": "replay-contract-v1", "objectiveSatisfied": true, "criteria": [], "remainingWork": [] }, "evidence": [], "verification": [], "attentionRequests": [], "artifacts": [], "futureResultAnnotation": { "safe": true } }
+}
diff --git a/packages/paperclip-runner/protocol/fixtures/replay/unsupported-required-version.json b/packages/paperclip-runner/protocol/fixtures/replay/unsupported-required-version.json
new file mode 100644
index 0000000000..f8c63b4e46
--- /dev/null
+++ b/packages/paperclip-runner/protocol/fixtures/replay/unsupported-required-version.json
@@ -0,0 +1,13 @@
+{
+  "schema": "paperclip.prp.fixture.v1", "fixtureVersion": 1, "protocolVersion": 2,
+  "name": "Unsupported required version", "description": "A fixture that requires PRP v2 must fail closed in a PRP v1 consumer.",
+  "identity": { "schema": "paperclip.prp.identity.v1", "companyId": "company_replay", "issueId": "issue_replay_v2", "runId": "run_replay_v2", "environmentLeaseId": "lease_replay_v2", "runnerInstanceId": "runner_replay", "normalizedSessionId": "session_replay_v2", "driverSessionId": "driver_replay_v2" },
+  "capabilities": { "schema": "paperclip.prp.capabilities.v1", "sessionReusePolicy": "new_per_run", "driver": { "kind": "future", "version": "2.0.0" }, "steer": true, "interrupt": true, "resume": true, "runtimeRequests": true, "structuredResult": true, "typedEvents": true },
+  "commands": [{ "schema": "paperclip.prp.command.v1", "commandId": "command_v2_prepare", "controllerSeq": 1, "type": "run.prepare", "issuedAt": "2026-08-07T13:00:00.000Z", "payload": {} }],
+  "events": [
+    { "schema": "paperclip.prp.event.v1", "sourceEventId": "event_v2_01", "sourceSeq": 1, "sourceInstanceId": "runner_replay", "sourceKind": "runner", "runId": "run_replay_v2", "normalizedSessionId": "session_replay_v2", "eventType": "run.result.proposed", "schemaVersion": 1, "priority": 0, "emittedAt": "2026-08-07T13:00:00.010Z", "payload": { "schema": "paperclip.run_result.v1", "reportedWorkDisposition": "done", "summary": "This result requires PRP v2.", "completionClaim": { "contractRevision": "replay-contract-v2", "objectiveSatisfied": true, "criteria": [], "remainingWork": [] }, "evidence": [], "verification": [], "attentionRequests": [], "artifacts": [] } },
+    { "schema": "paperclip.prp.event.v1", "sourceEventId": "event_v2_02", "sourceSeq": 2, "sourceInstanceId": "runner_replay", "sourceKind": "runner", "runId": "run_replay_v2", "normalizedSessionId": "session_replay_v2", "eventType": "run.terminal", "schemaVersion": 1, "priority": 0, "emittedAt": "2026-08-07T13:00:00.020Z", "payload": { "schema": "paperclip.prp.terminal.v1", "turnTerminalState": "completed", "runTerminalState": "succeeded", "reportedWorkDisposition": "done" } }
+  ],
+  "requests": [],
+  "result": { "schema": "paperclip.run_result.v1", "reportedWorkDisposition": "done", "summary": "This result requires PRP v2.", "completionClaim": { "contractRevision": "replay-contract-v2", "objectiveSatisfied": true, "criteria": [], "remainingWork": [] }, "evidence": [], "verification": [], "attentionRequests": [], "artifacts": [] }
+}
diff --git a/packages/paperclip-runner/protocol/manifest.json b/packages/paperclip-runner/protocol/manifest.json
new file mode 100644
index 0000000000..7aded07243
--- /dev/null
+++ b/packages/paperclip-runner/protocol/manifest.json
@@ -0,0 +1,173 @@
+{
+  "schema": "paperclip.prp.contract_manifest.v1",
+  "protocolVersion": 1,
+  "fixtureVersion": 1,
+  "generatedFrom": [
+    "protocol/schemas",
+    "protocol/fixtures"
+  ],
+  "schemas": [
+    {
+      "path": "schemas/capabilities.schema.json",
+      "id": "https://paperclip.dev/schemas/prp/v1/capabilities.schema.json",
+      "sha256": "e62a80328e5edde136b35463033280922ac2220575a83046b07fe034d233db88"
+    },
+    {
+      "path": "schemas/command.schema.json",
+      "id": "https://paperclip.dev/schemas/prp/v1/command.schema.json",
+      "sha256": "fc813e6b4d5b7e6890b496bd69848ada25dba58adbf7cf04163ca9e9bf2bcb79"
+    },
+    {
+      "path": "schemas/conformance-fixture.schema.json",
+      "id": "https://paperclip.dev/schemas/prp/v1/conformance-fixture.schema.json",
+      "sha256": "0febc66d128da1f251f9e932d78353a67f47ee60b7427e0a347c287bb6b7ea79"
+    },
+    {
+      "path": "schemas/conformance-output.schema.json",
+      "id": "https://paperclip.dev/schemas/prp/v1/conformance-output.schema.json",
+      "sha256": "96f78846dffc4a8300184751b9943214506f32ee1f393c6c0c453b666cf12d59"
+    },
+    {
+      "path": "schemas/event.schema.json",
+      "id": "https://paperclip.dev/schemas/prp/v1/event.schema.json",
+      "sha256": "b930af4a187c26312b4fff66813498b95332cb4e972f8b9282cdceafdf0de32c"
+    },
+    {
+      "path": "schemas/fixture.schema.json",
+      "id": "https://paperclip.dev/schemas/prp/v1/fixture.schema.json",
+      "sha256": "8ac87c2d8c639981277b5f72b9757a95badf85ff482d11596e4c63e01c616cba"
+    },
+    {
+      "path": "schemas/identity.schema.json",
+      "id": "https://paperclip.dev/schemas/prp/v1/identity.schema.json",
+      "sha256": "8a8a1943f14c739284daa241c5189f3b8026c050472c4f9909897456da506f48"
+    },
+    {
+      "path": "schemas/provider-descriptor.schema.json",
+      "id": "https://paperclip.dev/schemas/prp/v1/provider-descriptor.schema.json",
+      "sha256": "26e8af9314f1ca49578bfbacdcc111332225b422ea4ff68918a25ddac59129a6"
+    },
+    {
+      "path": "schemas/provider-event.schema.json",
+      "id": "https://paperclip.dev/schemas/prp/v1/provider-event.schema.json",
+      "sha256": "84521ea87ae782a7c07d1ef68b70f87fc4c436e79951a8076b7ba55e923fa88b"
+    },
+    {
+      "path": "schemas/question-adapter-fixture.schema.json",
+      "id": "https://paperclip.dev/schemas/prp/v1/question-adapter-fixture.schema.json",
+      "sha256": "002062abb4df9a98c92003eb4af43afbe8bdedd15d08b8697ad221fcc28ad9c7"
+    },
+    {
+      "path": "schemas/question-response.schema.json",
+      "id": "https://paperclip.dev/schemas/prp/v1/question-response.schema.json",
+      "sha256": "dec308b0daa4d882deb3878a1ad6ae5360f3342060f63ca636d65d1d9af1e055"
+    },
+    {
+      "path": "schemas/question-set.schema.json",
+      "id": "https://paperclip.dev/schemas/prp/v1/question-set.schema.json",
+      "sha256": "3bda40311ae3153bbf9d4a8c59f716680e17d711a4db3570193963918359751c"
+    },
+    {
+      "path": "schemas/request.schema.json",
+      "id": "https://paperclip.dev/schemas/prp/v1/request.schema.json",
+      "sha256": "bd41f01c00eddc1b635d3131a7183ddb616ff8fe68d5e348ddd9593a674c8d8e"
+    },
+    {
+      "path": "schemas/result.schema.json",
+      "id": "https://paperclip.dev/schemas/prp/v1/result.schema.json",
+      "sha256": "90f02c0a96e8ab9f75970fd788b61c18ccbd9abbd005bedfba280701729adce0"
+    },
+    {
+      "path": "schemas/semantic-tool.schema.json",
+      "id": "https://paperclip.dev/schemas/prp/v1/semantic-tool.schema.json",
+      "sha256": "f53f6832c0d65caaccf540662fdb08cf62d9bab45a18def7b559c4068ef54efc"
+    },
+    {
+      "path": "schemas/stop-reason.schema.json",
+      "id": "https://paperclip.dev/schemas/prp/v1/stop-reason.schema.json",
+      "sha256": "ed0c0807904ff1198273458057e1a565e828dba499372c0c80e2c69a1d600a13"
+    },
+    {
+      "path": "schemas/terminal.schema.json",
+      "id": "https://paperclip.dev/schemas/prp/v1/terminal.schema.json",
+      "sha256": "e9093399ac6422e77b060269910ffaba9a3d574ed578832821e310a0582edffd"
+    },
+    {
+      "path": "schemas/usage.schema.json",
+      "id": "https://paperclip.dev/schemas/prp/v1/usage.schema.json",
+      "sha256": "28fdbb3202095144649dddc438e6270c66d599c6f7e86838687f58d644726456"
+    },
+    {
+      "path": "schemas/workspace-diff.schema.json",
+      "id": "https://paperclip.dev/schemas/prp/v1/workspace-diff.schema.json",
+      "sha256": "f71b21f41cfc4c40aeaa503d1981d29355b4dd8b15036fcf3d8df5c35f8b8f6f"
+    },
+    {
+      "path": "schemas/workspace-file-reference.schema.json",
+      "id": "https://paperclip.dev/schemas/prp/v1/workspace-file-reference.schema.json",
+      "sha256": "0ab57e76c9710f520ed9d15cc5d0f25c68176beff3aff556ad62dba9b922eb23"
+    }
+  ],
+  "fixtures": [
+    {
+      "path": "fixtures/conformance-expected-output.json",
+      "sha256": "5a643639c9df0a2925ba95c5c5dfa2217605018bfa0dd3954ab4aca5fcfdc2c6",
+      "expectation": "accept",
+      "compatibilityCase": "cross-language-output"
+    },
+    {
+      "path": "fixtures/conformance-minimal-run.json",
+      "sha256": "1e4304bcb51c3d7aa0575cf47b1ff3901700a254a60cf7432003ce9af0175e3a",
+      "expectation": "accept",
+      "compatibilityCase": "cross-language-input"
+    },
+    {
+      "path": "fixtures/questions/codex.json",
+      "sha256": "ad673b6f9d70b74b53656e622d15fad1a66430f39d62b9ef71479d194a198bd6",
+      "expectation": "accept",
+      "compatibilityCase": "codex-structured-input"
+    },
+    {
+      "path": "fixtures/replay/duplicate-event.json",
+      "sha256": "779c146966d2825ffcde88bfff8b1fb238c162d40c578980ad3bd1a7def405d7",
+      "expectation": "accept",
+      "compatibilityCase": "canonical"
+    },
+    {
+      "path": "fixtures/replay/failed-run.json",
+      "sha256": "59281021b6ff11e4765213043580fc91eca8a02bedb3fe0c012bef9ad807da12",
+      "expectation": "accept",
+      "compatibilityCase": "canonical"
+    },
+    {
+      "path": "fixtures/replay/happy-path.json",
+      "sha256": "dfe0aeb4e7a217f8d375afe6e6d1ab0151bb8e81921b07ae0aaa6c4d0b8f8a1d",
+      "expectation": "accept",
+      "compatibilityCase": "canonical"
+    },
+    {
+      "path": "fixtures/replay/interrupted-run.json",
+      "sha256": "2056789605ffde847b3272e751226ce4be61527f6aaa4fe3f5557a621af0ad5c",
+      "expectation": "accept",
+      "compatibilityCase": "canonical"
+    },
+    {
+      "path": "fixtures/replay/source-gap.json",
+      "sha256": "d8a3eb2861e8198226360e666e5296ff5d7215f81d255a273b21d2bfe7dcc2ef",
+      "expectation": "accept",
+      "compatibilityCase": "canonical"
+    },
+    {
+      "path": "fixtures/replay/unknown-optional-fields.json",
+      "sha256": "4dbc4b70c299fe21791ca66949f3cb189c8f76514b62c52f5f40a489a84515c4",
+      "expectation": "accept",
+      "compatibilityCase": "additive-optional-fields"
+    },
+    {
+      "path": "fixtures/replay/unsupported-required-version.json",
+      "sha256": "60ac964d2cf49dc80ada0cb9c946b25952f3e2be10719801d3f2f8bd98d27699",
+      "expectation": "reject",
+      "compatibilityCase": "unknown-required-version"
+    }
+  ]
+}
diff --git a/packages/paperclip-runner/protocol/schemas/capabilities.schema.json b/packages/paperclip-runner/protocol/schemas/capabilities.schema.json
new file mode 100644
index 0000000000..fdaf331bb5
--- /dev/null
+++ b/packages/paperclip-runner/protocol/schemas/capabilities.schema.json
@@ -0,0 +1,98 @@
+{
+  "$schema": "https://json-schema.org/draft/2020-12/schema",
+  "$id": "https://paperclip.dev/schemas/prp/v1/capabilities.schema.json",
+  "title": "PRP negotiated capabilities",
+  "type": "object",
+  "required": [
+    "schema",
+    "sessionReusePolicy",
+    "driver",
+    "steer",
+    "interrupt",
+    "resume",
+    "runtimeRequests",
+    "structuredResult",
+    "typedEvents"
+  ],
+  "properties": {
+    "schema": { "const": "paperclip.prp.capabilities.v1" },
+    "sessionReusePolicy": {
+      "enum": ["new_per_run", "reuse_per_issue", "reuse_per_workspace"]
+    },
+    "driver": {
+      "type": "object",
+      "required": ["kind", "version"],
+      "properties": {
+        "kind": { "type": "string", "minLength": 1, "maxLength": 80 },
+        "version": { "type": "string", "minLength": 1, "maxLength": 80 }
+      },
+      "additionalProperties": true
+    },
+    "steer": { "type": "boolean" },
+    "interrupt": { "type": "boolean" },
+    "resume": { "type": "boolean" },
+    "runtimeRequests": { "type": "boolean" },
+    "structuredResult": { "type": "boolean" },
+    "typedEvents": { "type": "boolean" },
+    "typedEventFamilies": {
+      "type": "array",
+      "maxItems": 64,
+      "items": {
+        "type": "object",
+        "required": ["family", "version", "availability", "detailLevel"],
+        "properties": {
+          "family": { "type": "string", "minLength": 1, "maxLength": 160, "pattern": "^[a-z][a-z0-9_.-]*$" },
+          "version": { "const": 1 },
+          "availability": { "enum": ["available", "unsupported", "policy_disabled"] },
+          "detailLevel": { "enum": ["summary", "structured"] }
+        },
+        "additionalProperties": false
+      }
+    },
+    "semanticTools": {
+      "type": "object",
+      "required": ["schema", "schemaVersion", "operations"],
+      "properties": {
+        "schema": { "const": "paperclip.prp.semantic_tools.v1" },
+        "schemaVersion": { "const": 1 },
+        "operations": {
+          "type": "array",
+          "items": {
+            "type": "object",
+            "required": ["operationId", "version", "availability", "redactionDisposition"],
+            "properties": {
+              "operationId": {
+                "type": "string",
+                "minLength": 1,
+                "maxLength": 160,
+                "pattern": "^[A-Za-z0-9][A-Za-z0-9._:-]*$"
+              },
+              "version": { "const": 1 },
+              "availability": { "enum": ["available", "denied", "unsupported"] },
+              "redactionDisposition": { "const": "digest_only" },
+              "requiredClaims": {
+                "type": "array",
+                "items": { "type": "string", "minLength": 1, "maxLength": 160 },
+                "uniqueItems": true
+              },
+              "reasonCode": {
+                "type": "string",
+                "minLength": 1,
+                "maxLength": 160,
+                "pattern": "^[a-z][a-z0-9_.:-]*$"
+              }
+            },
+            "additionalProperties": true
+          }
+        }
+      },
+      "additionalProperties": true
+    },
+    "unsupported": {
+      "type": "array",
+      "items": { "type": "string", "minLength": 1 },
+      "uniqueItems": true
+    }
+  },
+  "additionalProperties": true
+}
diff --git a/packages/paperclip-runner/protocol/schemas/command.schema.json b/packages/paperclip-runner/protocol/schemas/command.schema.json
new file mode 100644
index 0000000000..b6ae97cca7
--- /dev/null
+++ b/packages/paperclip-runner/protocol/schemas/command.schema.json
@@ -0,0 +1,48 @@
+{
+  "$schema": "https://json-schema.org/draft/2020-12/schema",
+  "$id": "https://paperclip.dev/schemas/prp/v1/command.schema.json",
+  "title": "PRP runner command",
+  "type": "object",
+  "required": ["schema", "commandId", "controllerSeq", "type", "issuedAt", "payload"],
+  "properties": {
+    "schema": { "const": "paperclip.prp.command.v1" },
+    "commandId": { "type": "string", "minLength": 1, "maxLength": 160 },
+    "controllerSeq": { "type": "integer", "minimum": 1 },
+    "type": {
+      "enum": [
+        "run.prepare",
+        "run.attach",
+        "session.open",
+        "turn.start",
+        "turn.steer",
+        "turn.interrupt",
+        "turn.stop",
+        "request.resolve",
+        "interaction.receipt",
+        "semantic_tool.result",
+        "session.snapshot",
+        "session.close",
+        "session.budget.increase",
+        "session.destroy",
+        "run.cancel",
+        "runner.drain",
+        "runner.suspend",
+        "runner.shutdown"
+      ]
+    },
+    "issuedAt": { "type": "string", "format": "date-time" },
+    "deadlineAt": { "type": "string", "format": "date-time" },
+    "precondition": {
+      "type": "object",
+      "properties": {
+        "runnerState": { "type": "array", "items": { "type": "string" } },
+        "runState": { "type": "array", "items": { "type": "string" } },
+        "sessionState": { "type": "array", "items": { "type": "string" } },
+        "activeTurnId": { "type": ["string", "null"] }
+      },
+      "additionalProperties": true
+    },
+    "payload": { "type": "object", "additionalProperties": true }
+  },
+  "additionalProperties": true
+}
diff --git a/packages/paperclip-runner/protocol/schemas/conformance-fixture.schema.json b/packages/paperclip-runner/protocol/schemas/conformance-fixture.schema.json
new file mode 100644
index 0000000000..cae7cd0b4b
--- /dev/null
+++ b/packages/paperclip-runner/protocol/schemas/conformance-fixture.schema.json
@@ -0,0 +1,51 @@
+{
+  "$schema": "https://json-schema.org/draft/2020-12/schema",
+  "$id": "https://paperclip.dev/schemas/prp/v1/conformance-fixture.schema.json",
+  "title": "Paperclip Runner cross-language conformance fixture",
+  "type": "object",
+  "required": ["schemaVersion", "run", "events", "result"],
+  "properties": {
+    "schemaVersion": { "const": "paperclip.runner.conformance.fixture.v1" },
+    "run": {
+      "type": "object",
+      "required": ["runId", "sessionId", "companyId", "issueId", "agentId"],
+      "properties": {
+        "runId": { "$ref": "#/$defs/id" },
+        "sessionId": { "$ref": "#/$defs/id" },
+        "companyId": { "$ref": "#/$defs/id" },
+        "issueId": { "$ref": "#/$defs/id" },
+        "agentId": { "$ref": "#/$defs/id" }
+      },
+      "additionalProperties": true
+    },
+    "events": {
+      "type": "array",
+      "minItems": 1,
+      "items": {
+        "type": "object",
+        "required": ["eventId", "runId", "sequence", "type"],
+        "properties": {
+          "eventId": { "$ref": "#/$defs/id" },
+          "runId": { "$ref": "#/$defs/id" },
+          "sequence": { "type": "integer", "minimum": 1 },
+          "type": { "enum": ["run.started", "run.completed"] }
+        },
+        "additionalProperties": true
+      }
+    },
+    "result": {
+      "type": "object",
+      "required": ["runId", "status", "summary"],
+      "properties": {
+        "runId": { "$ref": "#/$defs/id" },
+        "status": { "enum": ["succeeded", "failed", "interrupted"] },
+        "summary": { "type": "string", "minLength": 1, "maxLength": 4000 }
+      },
+      "additionalProperties": true
+    }
+  },
+  "$defs": {
+    "id": { "type": "string", "minLength": 1, "maxLength": 160 }
+  },
+  "additionalProperties": true
+}
diff --git a/packages/paperclip-runner/protocol/schemas/conformance-output.schema.json b/packages/paperclip-runner/protocol/schemas/conformance-output.schema.json
new file mode 100644
index 0000000000..e348c75e4a
--- /dev/null
+++ b/packages/paperclip-runner/protocol/schemas/conformance-output.schema.json
@@ -0,0 +1,32 @@
+{
+  "$schema": "https://json-schema.org/draft/2020-12/schema",
+  "$id": "https://paperclip.dev/schemas/prp/v1/conformance-output.schema.json",
+  "title": "Paperclip Runner cross-language conformance output",
+  "type": "object",
+  "required": ["schemaVersion", "runIdentity", "result"],
+  "properties": {
+    "schemaVersion": { "const": "paperclip.runner.conformance.output.v1" },
+    "runIdentity": {
+      "type": "object",
+      "required": ["runId", "sessionId"],
+      "properties": {
+        "runId": { "$ref": "#/$defs/id" },
+        "sessionId": { "$ref": "#/$defs/id" }
+      },
+      "additionalProperties": true
+    },
+    "result": {
+      "type": "object",
+      "required": ["status", "summary"],
+      "properties": {
+        "status": { "enum": ["succeeded", "failed", "interrupted"] },
+        "summary": { "type": "string", "minLength": 1, "maxLength": 4000 }
+      },
+      "additionalProperties": true
+    }
+  },
+  "$defs": {
+    "id": { "type": "string", "minLength": 1, "maxLength": 160 }
+  },
+  "additionalProperties": true
+}
diff --git a/packages/paperclip-runner/protocol/schemas/event.schema.json b/packages/paperclip-runner/protocol/schemas/event.schema.json
new file mode 100644
index 0000000000..332e70b396
--- /dev/null
+++ b/packages/paperclip-runner/protocol/schemas/event.schema.json
@@ -0,0 +1,173 @@
+{
+  "$schema": "https://json-schema.org/draft/2020-12/schema",
+  "$id": "https://paperclip.dev/schemas/prp/v1/event.schema.json",
+  "title": "PRP native event",
+  "type": "object",
+  "required": [
+    "schema",
+    "sourceEventId",
+    "sourceSeq",
+    "sourceInstanceId",
+    "sourceKind",
+    "runId",
+    "eventType",
+    "schemaVersion",
+    "priority",
+    "emittedAt",
+    "payload"
+  ],
+  "properties": {
+    "schema": { "const": "paperclip.prp.event.v1" },
+    "sourceEventId": { "type": "string", "minLength": 1, "maxLength": 160 },
+    "sourceSeq": { "type": "integer", "minimum": 1 },
+    "sourceInstanceId": { "type": "string", "minLength": 1, "maxLength": 160 },
+    "sourceKind": { "enum": ["runner", "control_plane"] },
+    "runId": { "type": "string", "minLength": 1, "maxLength": 160 },
+    "normalizedSessionId": { "type": "string", "minLength": 1, "maxLength": 160 },
+    "turnId": { "type": "string", "minLength": 1, "maxLength": 160 },
+    "itemId": { "type": "string", "minLength": 1, "maxLength": 160 },
+    "eventType": {
+      "enum": [
+        "runner.connected", "runner.reconnected", "runner.reconciled", "runner.disconnected", "runner.draining", "runner.suspending", "runner.suspended", "runner.stopped", "runner.diagnostic",
+        "runtime.phase.changed", "sandbox.metric", "workspace.ready", "workspace.change.updated", "workspace.diff.recorded", "workspace.file.referenced",
+        "harness.starting", "harness.ready", "harness.exited", "harness.diagnostic",
+        "plan.updated",
+        "tool.execution.started", "tool.execution.progressed", "tool.execution.completed",
+        "research.started", "research.progressed", "research.completed",
+        "delegation.started", "delegation.updated", "delegation.completed",
+        "model.route.changed", "model.verification.updated", "context.compacted",
+        "artifact.viewed", "artifact.generated", "review.mode.changed",
+        "hook.started", "hook.completed", "memory.citation.referenced",
+        "safety.review.started", "safety.review.completed", "terminal.input.sent",
+        "wait.started", "wait.completed", "provider.notice.recorded",
+        "session.starting", "session.started", "session.resuming", "session.resumed", "session.reconciled", "session.updated", "session.closed", "session.failed",
+        "turn.submitted", "turn.accepted", "turn.started", "turn.completed", "turn.failed", "turn.interrupted", "turn.cancelled",
+        "item.started", "item.delta", "item.completed", "item.failed", "usage.reported",
+        "semantic_tool.input", "semantic_tool.result",
+        "mcp_app.discovered", "mcp_app.resource.resolved", "mcp_app.initializing", "mcp_app.ready", "mcp_app.tool_input", "mcp_app.tool_result", "mcp_app.action.requested", "mcp_app.action.resolved", "mcp_app.host_context.changed", "mcp_app.failed", "mcp_app.teardown",
+        "runtime_request.created", "runtime_request.resolved", "runtime_request.expired", "runtime_request.cancelled",
+        "interaction.request.proposed", "interaction.request.materialized", "interaction.request.rejected", "interaction.response.progressed", "interaction.response.resolved", "interaction.response.delivered",
+        "run.attached", "run.detached", "run.result.proposed", "run.result.accepted", "run.result.rejected",
+        "attention.request.proposed", "attention.request.routed", "attention.request.resolved", "attention.request.expired", "attention.request.superseded",
+        "work.assessment.recorded", "issue.status.decision.recorded", "issue.status.decision.applied", "issue.status.decision.rejected", "issue.status.decision.superseded",
+        "run.terminal"
+      ]
+    },
+    "schemaVersion": { "const": 1 },
+    "priority": { "enum": [0, 1, 2] },
+    "emittedAt": { "type": "string", "format": "date-time" },
+    "observedAt": { "type": "string", "format": "date-time" },
+    "payload": {
+      "type": "object",
+      "properties": {
+        "channel": { "enum": ["progress", "final", "summary", "detail", "unknown"] },
+        "providerPhase": { "type": "string" },
+        "providerMethod": { "type": "string" }
+      },
+      "additionalProperties": true
+    },
+    "debug": { "type": "object", "additionalProperties": true }
+  },
+  "allOf": [
+    { "if": { "properties": { "eventType": { "const": "plan.updated" } } }, "then": { "properties": { "payload": { "$ref": "https://paperclip.dev/schemas/prp/v1/provider-event.schema.json#/$defs/plan" } } } },
+    { "if": { "properties": { "eventType": { "enum": ["tool.execution.started", "tool.execution.progressed", "tool.execution.completed"] } } }, "then": { "properties": { "payload": { "$ref": "https://paperclip.dev/schemas/prp/v1/provider-event.schema.json#/$defs/toolExecution" } } } },
+    { "if": { "properties": { "eventType": { "enum": ["research.started", "research.progressed", "research.completed"] } } }, "then": { "properties": { "payload": { "$ref": "https://paperclip.dev/schemas/prp/v1/provider-event.schema.json#/$defs/research" } } } },
+    { "if": { "properties": { "eventType": { "enum": ["delegation.started", "delegation.updated", "delegation.completed"] } } }, "then": { "properties": { "payload": { "$ref": "https://paperclip.dev/schemas/prp/v1/provider-event.schema.json#/$defs/delegation" } } } },
+    { "if": { "properties": { "eventType": { "const": "model.route.changed" } } }, "then": { "properties": { "payload": { "$ref": "https://paperclip.dev/schemas/prp/v1/provider-event.schema.json#/$defs/modelRoute" } } } },
+    { "if": { "properties": { "eventType": { "const": "model.verification.updated" } } }, "then": { "properties": { "payload": { "$ref": "https://paperclip.dev/schemas/prp/v1/provider-event.schema.json#/$defs/modelVerification" } } } },
+    { "if": { "properties": { "eventType": { "const": "context.compacted" } } }, "then": { "properties": { "payload": { "$ref": "https://paperclip.dev/schemas/prp/v1/provider-event.schema.json#/$defs/contextCompacted" } } } },
+    { "if": { "properties": { "eventType": { "const": "artifact.viewed" } } }, "then": { "properties": { "payload": { "$ref": "https://paperclip.dev/schemas/prp/v1/provider-event.schema.json#/$defs/artifactViewed" } } } },
+    { "if": { "properties": { "eventType": { "const": "artifact.generated" } } }, "then": { "properties": { "payload": { "$ref": "https://paperclip.dev/schemas/prp/v1/provider-event.schema.json#/$defs/artifactGenerated" } } } },
+    { "if": { "properties": { "eventType": { "const": "review.mode.changed" } } }, "then": { "properties": { "payload": { "$ref": "https://paperclip.dev/schemas/prp/v1/provider-event.schema.json#/$defs/reviewMode" } } } },
+    { "if": { "properties": { "eventType": { "enum": ["hook.started", "hook.completed"] } } }, "then": { "properties": { "payload": { "$ref": "https://paperclip.dev/schemas/prp/v1/provider-event.schema.json#/$defs/hook" } } } },
+    { "if": { "properties": { "eventType": { "const": "memory.citation.referenced" } } }, "then": { "properties": { "payload": { "$ref": "https://paperclip.dev/schemas/prp/v1/provider-event.schema.json#/$defs/memoryCitation" } } } },
+    { "if": { "properties": { "eventType": { "enum": ["safety.review.started", "safety.review.completed"] } } }, "then": { "properties": { "payload": { "$ref": "https://paperclip.dev/schemas/prp/v1/provider-event.schema.json#/$defs/safetyReview" } } } },
+    { "if": { "properties": { "eventType": { "const": "terminal.input.sent" } } }, "then": { "properties": { "payload": { "$ref": "https://paperclip.dev/schemas/prp/v1/provider-event.schema.json#/$defs/terminalInput" } } } },
+    { "if": { "properties": { "eventType": { "enum": ["wait.started", "wait.completed"] } } }, "then": { "properties": { "payload": { "$ref": "https://paperclip.dev/schemas/prp/v1/provider-event.schema.json#/$defs/wait" } } } },
+    { "if": { "properties": { "eventType": { "const": "provider.notice.recorded" } } }, "then": { "properties": { "payload": { "$ref": "https://paperclip.dev/schemas/prp/v1/provider-event.schema.json#/$defs/providerNotice" } } } },
+    {
+      "if": { "properties": { "eventType": { "const": "workspace.file.referenced" } } },
+      "then": {
+        "properties": {
+          "payload": { "$ref": "https://paperclip.dev/schemas/prp/v1/workspace-file-reference.schema.json" }
+        }
+      }
+    },
+    {
+      "if": { "properties": { "eventType": { "enum": ["workspace.change.updated", "workspace.diff.recorded"] } } },
+      "then": {
+        "properties": {
+          "payload": { "$ref": "https://paperclip.dev/schemas/prp/v1/workspace-diff.schema.json" }
+        }
+      }
+    },
+    {
+      "if": { "properties": { "eventType": { "const": "workspace.diff.recorded" } } },
+      "then": {
+        "properties": {
+          "payload": {
+            "allOf": [
+              { "$ref": "https://paperclip.dev/schemas/prp/v1/workspace-diff.schema.json" },
+              { "type": "object", "properties": { "complete": { "const": true } } }
+            ]
+          }
+        }
+      }
+    },
+    {
+      "if": { "properties": { "eventType": { "enum": ["semantic_tool.input", "mcp_app.tool_input"] } } },
+      "then": {
+        "properties": {
+          "payload": {
+            "type": "object",
+            "properties": {
+              "semantic_tool": {
+                "allOf": [
+                  { "$ref": "https://paperclip.dev/schemas/prp/v1/semantic-tool.schema.json" },
+                  { "type": "object", "properties": { "phase": { "const": "input" } } }
+                ]
+              }
+            },
+            "additionalProperties": true
+          }
+        }
+      }
+    },
+    {
+      "if": { "properties": { "eventType": { "enum": ["semantic_tool.result", "mcp_app.tool_result"] } } },
+      "then": {
+        "properties": {
+          "payload": {
+            "type": "object",
+            "properties": {
+              "semantic_tool": {
+                "allOf": [
+                  { "$ref": "https://paperclip.dev/schemas/prp/v1/semantic-tool.schema.json" },
+                  { "type": "object", "properties": { "phase": { "const": "result" } } }
+                ]
+              }
+            },
+            "additionalProperties": true
+          }
+        }
+      }
+    },
+    {
+      "if": { "properties": { "eventType": { "const": "run.terminal" } } },
+      "then": {
+        "properties": {
+          "payload": { "$ref": "https://paperclip.dev/schemas/prp/v1/terminal.schema.json" }
+        }
+      }
+    },
+    {
+      "if": { "properties": { "eventType": { "const": "run.result.proposed" } } },
+      "then": {
+        "properties": {
+          "payload": { "$ref": "https://paperclip.dev/schemas/prp/v1/result.schema.json" }
+        }
+      }
+    }
+  ],
+  "additionalProperties": true
+}
diff --git a/packages/paperclip-runner/protocol/schemas/fixture.schema.json b/packages/paperclip-runner/protocol/schemas/fixture.schema.json
new file mode 100644
index 0000000000..18d33ade54
--- /dev/null
+++ b/packages/paperclip-runner/protocol/schemas/fixture.schema.json
@@ -0,0 +1,42 @@
+{
+  "$schema": "https://json-schema.org/draft/2020-12/schema",
+  "$id": "https://paperclip.dev/schemas/prp/v1/fixture.schema.json",
+  "title": "PRP scripted replay fixture",
+  "type": "object",
+  "required": [
+    "schema",
+    "fixtureVersion",
+    "protocolVersion",
+    "name",
+    "description",
+    "identity",
+    "capabilities",
+    "commands",
+    "events",
+    "result"
+  ],
+  "properties": {
+    "schema": { "const": "paperclip.prp.fixture.v1" },
+    "fixtureVersion": { "const": 1 },
+    "protocolVersion": { "const": 1 },
+    "name": { "type": "string", "minLength": 1, "maxLength": 120 },
+    "description": { "type": "string", "minLength": 1, "maxLength": 1000 },
+    "identity": { "$ref": "https://paperclip.dev/schemas/prp/v1/identity.schema.json" },
+    "capabilities": { "$ref": "https://paperclip.dev/schemas/prp/v1/capabilities.schema.json" },
+    "commands": {
+      "type": "array",
+      "items": { "$ref": "https://paperclip.dev/schemas/prp/v1/command.schema.json" }
+    },
+    "events": {
+      "type": "array",
+      "minItems": 1,
+      "items": { "$ref": "https://paperclip.dev/schemas/prp/v1/event.schema.json" }
+    },
+    "requests": {
+      "type": "array",
+      "items": { "$ref": "https://paperclip.dev/schemas/prp/v1/request.schema.json" }
+    },
+    "result": { "$ref": "https://paperclip.dev/schemas/prp/v1/result.schema.json" }
+  },
+  "additionalProperties": true
+}
diff --git a/packages/paperclip-runner/protocol/schemas/identity.schema.json b/packages/paperclip-runner/protocol/schemas/identity.schema.json
new file mode 100644
index 0000000000..8279ef857c
--- /dev/null
+++ b/packages/paperclip-runner/protocol/schemas/identity.schema.json
@@ -0,0 +1,36 @@
+{
+  "$schema": "https://json-schema.org/draft/2020-12/schema",
+  "$id": "https://paperclip.dev/schemas/prp/v1/identity.schema.json",
+  "title": "PRP identity graph",
+  "type": "object",
+  "required": [
+    "schema",
+    "companyId",
+    "issueId",
+    "runId",
+    "environmentLeaseId",
+    "runnerInstanceId",
+    "normalizedSessionId",
+    "driverSessionId"
+  ],
+  "properties": {
+    "schema": { "const": "paperclip.prp.identity.v1" },
+    "companyId": { "$ref": "#/$defs/stableId" },
+    "issueId": { "$ref": "#/$defs/stableId" },
+    "runId": { "$ref": "#/$defs/stableId" },
+    "environmentLeaseId": { "$ref": "#/$defs/stableId" },
+    "runnerInstanceId": { "$ref": "#/$defs/stableId" },
+    "normalizedSessionId": { "$ref": "#/$defs/stableId" },
+    "driverSessionId": { "$ref": "#/$defs/stableId" },
+    "providerSessionId": { "$ref": "#/$defs/stableId" }
+  },
+  "additionalProperties": true,
+  "$defs": {
+    "stableId": {
+      "type": "string",
+      "minLength": 1,
+      "maxLength": 160,
+      "pattern": "^[A-Za-z0-9][A-Za-z0-9._:-]*$"
+    }
+  }
+}
diff --git a/packages/paperclip-runner/protocol/schemas/provider-descriptor.schema.json b/packages/paperclip-runner/protocol/schemas/provider-descriptor.schema.json
new file mode 100644
index 0000000000..3bfbb66a06
--- /dev/null
+++ b/packages/paperclip-runner/protocol/schemas/provider-descriptor.schema.json
@@ -0,0 +1,17 @@
+{
+  "$schema": "https://json-schema.org/draft/2020-12/schema",
+  "$id": "https://paperclip.dev/schemas/prp/v1/provider-descriptor.schema.json",
+  "title": "PRP provider runtime descriptor",
+  "type": "object",
+  "required": ["provider", "driver", "model", "executionKind", "providerVersion"],
+  "properties": {
+    "provider": { "const": "codex" },
+    "driver": { "const": "codex_app_server" },
+    "model": { "type": ["string", "null"], "maxLength": 240 },
+    "executionKind": { "const": "local_process" },
+    "providerVersion": { "type": "string", "minLength": 1, "maxLength": 120 },
+    "providerSessionId": { "type": ["string", "null"], "maxLength": 240 },
+    "processId": { "type": ["integer", "null"], "minimum": 1 }
+  },
+  "additionalProperties": true
+}
diff --git a/packages/paperclip-runner/protocol/schemas/provider-event.schema.json b/packages/paperclip-runner/protocol/schemas/provider-event.schema.json
new file mode 100644
index 0000000000..8af5200ddf
--- /dev/null
+++ b/packages/paperclip-runner/protocol/schemas/provider-event.schema.json
@@ -0,0 +1,167 @@
+{
+  "$schema": "https://json-schema.org/draft/2020-12/schema",
+  "$id": "https://paperclip.dev/schemas/prp/v1/provider-event.schema.json",
+  "title": "Provider-neutral runner activity payload",
+  "oneOf": [
+    { "$ref": "#/$defs/plan" },
+    { "$ref": "#/$defs/toolExecution" },
+    { "$ref": "#/$defs/research" },
+    { "$ref": "#/$defs/delegation" },
+    { "$ref": "#/$defs/modelRoute" },
+    { "$ref": "#/$defs/modelVerification" },
+    { "$ref": "#/$defs/contextCompacted" },
+    { "$ref": "#/$defs/artifactViewed" },
+    { "$ref": "#/$defs/artifactGenerated" },
+    { "$ref": "#/$defs/reviewMode" },
+    { "$ref": "#/$defs/hook" },
+    { "$ref": "#/$defs/memoryCitation" },
+    { "$ref": "#/$defs/safetyReview" },
+    { "$ref": "#/$defs/terminalInput" },
+    { "$ref": "#/$defs/wait" },
+    { "$ref": "#/$defs/providerNotice" }
+  ],
+  "$defs": {
+    "id": { "type": "string", "minLength": 1, "maxLength": 160, "pattern": "^[A-Za-z0-9][A-Za-z0-9._:-]*$" },
+    "shortText": { "type": "string", "maxLength": 4000 },
+    "nullableShortText": { "type": ["string", "null"], "maxLength": 4000 },
+    "safePath": { "type": ["string", "null"], "maxLength": 4096, "pattern": "^(?!/)(?!.*(?:^|/)\\.\\.(?:/|$)).*$" },
+    "safeUrl": { "type": ["string", "null"], "maxLength": 8192, "pattern": "^https?://" },
+    "plan": {
+      "type": "object",
+      "required": ["schema", "planId", "revision", "steps", "complete", "syncStatus"],
+      "properties": {
+        "schema": { "const": "paperclip.plan.updated.v1" },
+        "planId": { "$ref": "#/$defs/id" },
+        "revision": { "type": "integer", "minimum": 1 },
+        "explanation": { "$ref": "#/$defs/nullableShortText" },
+        "steps": { "type": "array", "maxItems": 256, "items": { "type": "object", "required": ["stepId", "body", "status"], "properties": { "stepId": { "$ref": "#/$defs/id" }, "body": { "$ref": "#/$defs/shortText" }, "status": { "enum": ["pending", "in_progress", "completed", "blocked"] } }, "additionalProperties": false } },
+        "complete": { "type": "boolean" },
+        "syncStatus": { "enum": ["streaming", "pending", "synchronized", "conflict", "not_applicable"] },
+        "documentRevision": { "type": ["integer", "null"], "minimum": 1 }
+      },
+      "additionalProperties": false
+    },
+    "toolExecution": {
+      "type": "object",
+      "required": ["schema", "executionId", "transport", "operation", "status", "output", "outputBytes", "outputTruncated", "outputDigest"],
+      "properties": {
+        "schema": { "const": "paperclip.tool.execution.v1" },
+        "executionId": { "$ref": "#/$defs/id" },
+        "transport": { "enum": ["process", "mcp", "dynamic", "builtin"] },
+        "operation": { "enum": ["read", "search", "list", "execute", "edit", "unknown"] },
+        "name": { "$ref": "#/$defs/nullableShortText" },
+        "target": { "$ref": "#/$defs/safePath" },
+        "namespace": { "type": ["string", "null"], "maxLength": 240 },
+        "readOnly": { "type": ["boolean", "null"] },
+        "status": { "enum": ["running", "completed", "failed", "cancelled", "interrupted"] },
+        "durationMs": { "type": ["integer", "null"], "minimum": 0 },
+        "exitCode": { "type": ["integer", "null"] },
+        "progress": { "$ref": "#/$defs/nullableShortText" },
+        "output": { "type": ["string", "null"], "maxLength": 65536 },
+        "outputBytes": { "type": "integer", "minimum": 0 },
+        "outputTruncated": { "type": "boolean" },
+        "outputDigest": { "type": ["string", "null"], "pattern": "^sha256:[a-f0-9]{64}$" }
+      },
+      "additionalProperties": false
+    },
+    "research": {
+      "type": "object",
+      "required": ["schema", "researchId", "action", "status", "sources"],
+      "properties": {
+        "schema": { "const": "paperclip.research.v1" },
+        "researchId": { "$ref": "#/$defs/id" },
+        "action": { "enum": ["search", "open_page", "find_in_page", "other"] },
+        "status": { "enum": ["running", "completed", "failed", "cancelled"] },
+        "query": { "$ref": "#/$defs/nullableShortText" },
+        "url": { "$ref": "#/$defs/safeUrl" },
+        "pattern": { "$ref": "#/$defs/nullableShortText" },
+        "sources": { "type": "array", "maxItems": 64, "items": { "type": "object", "required": ["sourceId", "title", "url", "snippet"], "properties": { "sourceId": { "$ref": "#/$defs/id" }, "title": { "$ref": "#/$defs/shortText" }, "url": { "$ref": "#/$defs/safeUrl" }, "snippet": { "$ref": "#/$defs/nullableShortText" } }, "additionalProperties": false } }
+      },
+      "additionalProperties": false
+    },
+    "delegation": {
+      "type": "object",
+      "required": ["schema", "delegationId", "action", "status", "children"],
+      "properties": {
+        "schema": { "const": "paperclip.delegation.v1" },
+        "delegationId": { "$ref": "#/$defs/id" },
+        "action": { "enum": ["spawn", "message", "resume", "wait", "close"] },
+        "status": { "enum": ["running", "waiting", "completed", "failed", "interrupted", "closed"] },
+        "children": { "type": "array", "maxItems": 64, "items": { "type": "object", "required": ["childId", "role", "model", "status", "summary", "activitySummary"], "properties": { "childId": { "$ref": "#/$defs/id" }, "role": { "type": ["string", "null"], "maxLength": 160 }, "model": { "type": ["string", "null"], "maxLength": 240 }, "status": { "enum": ["running", "waiting", "completed", "failed", "interrupted", "closed"] }, "summary": { "$ref": "#/$defs/nullableShortText" }, "activitySummary": { "$ref": "#/$defs/nullableShortText" } }, "additionalProperties": false } }
+      },
+      "additionalProperties": false
+    },
+    "modelRoute": {
+      "type": "object",
+      "required": ["schema", "routeId", "provider", "requestedModel", "fromModel", "effectiveModel", "reason"],
+      "properties": { "schema": { "const": "paperclip.model.route_changed.v1" }, "routeId": { "$ref": "#/$defs/id" }, "provider": { "type": "string", "minLength": 1, "maxLength": 160 }, "requestedModel": { "type": "string", "minLength": 1, "maxLength": 240 }, "fromModel": { "type": ["string", "null"], "maxLength": 240 }, "effectiveModel": { "type": "string", "minLength": 1, "maxLength": 240 }, "reason": { "$ref": "#/$defs/shortText" } },
+      "additionalProperties": false
+    },
+    "modelVerification": {
+      "type": "object",
+      "required": ["schema", "verificationId", "status", "classes", "buffering", "summary"],
+      "properties": { "schema": { "const": "paperclip.model.verification.v1" }, "verificationId": { "$ref": "#/$defs/id" }, "status": { "enum": ["running", "completed", "failed"] }, "classes": { "type": "array", "maxItems": 32, "items": { "type": "string", "maxLength": 160 } }, "buffering": { "type": "boolean" }, "summary": { "$ref": "#/$defs/nullableShortText" } },
+      "additionalProperties": false
+    },
+    "contextCompacted": {
+      "type": "object",
+      "required": ["schema", "compactionId", "reason", "preTokens", "postTokens", "sameSession"],
+      "properties": { "schema": { "const": "paperclip.context.compacted.v1" }, "compactionId": { "$ref": "#/$defs/id" }, "reason": { "enum": ["context_window", "manual", "provider", "unknown"] }, "preTokens": { "type": ["integer", "null"], "minimum": 0 }, "postTokens": { "type": ["integer", "null"], "minimum": 0 }, "sameSession": { "type": "boolean" } },
+      "additionalProperties": false
+    },
+    "artifactViewed": {
+      "type": "object",
+      "required": ["schema", "artifactId", "reference", "mediaType", "title"],
+      "properties": { "schema": { "const": "paperclip.artifact.viewed.v1" }, "artifactId": { "$ref": "#/$defs/id" }, "reference": { "$ref": "#/$defs/safePath" }, "mediaType": { "type": ["string", "null"], "maxLength": 160 }, "title": { "$ref": "#/$defs/nullableShortText" } },
+      "additionalProperties": false
+    },
+    "artifactGenerated": {
+      "type": "object",
+      "required": ["schema", "artifactId", "status", "reference", "mediaType", "registered", "failure"],
+      "properties": { "schema": { "const": "paperclip.artifact.generated.v1" }, "artifactId": { "$ref": "#/$defs/id" }, "status": { "enum": ["running", "completed", "failed"] }, "reference": { "$ref": "#/$defs/safePath" }, "mediaType": { "type": ["string", "null"], "maxLength": 160 }, "registered": { "type": "boolean" }, "transparentBackground": { "type": ["boolean", "null"] }, "failure": { "$ref": "#/$defs/nullableShortText" } },
+      "additionalProperties": false
+    },
+    "reviewMode": {
+      "type": "object",
+      "required": ["schema", "reviewId", "state", "scope"],
+      "properties": { "schema": { "const": "paperclip.review.mode_changed.v1" }, "reviewId": { "$ref": "#/$defs/id" }, "state": { "enum": ["entered", "exited"] }, "scope": { "$ref": "#/$defs/nullableShortText" } },
+      "additionalProperties": false
+    },
+    "hook": {
+      "type": "object",
+      "required": ["schema", "hookId", "event", "scope", "status", "blocking", "durationMs", "summary"],
+      "properties": { "schema": { "const": "paperclip.hook.v1" }, "hookId": { "$ref": "#/$defs/id" }, "event": { "type": "string", "minLength": 1, "maxLength": 160 }, "scope": { "type": "string", "minLength": 1, "maxLength": 160 }, "status": { "enum": ["running", "completed", "failed", "cancelled"] }, "blocking": { "type": "boolean" }, "durationMs": { "type": ["integer", "null"], "minimum": 0 }, "summary": { "$ref": "#/$defs/nullableShortText" } },
+      "additionalProperties": false
+    },
+    "memoryCitation": {
+      "type": "object",
+      "required": ["schema", "citationId", "messageItemId", "label", "available", "reference"],
+      "properties": { "schema": { "const": "paperclip.memory.citation.v1" }, "citationId": { "$ref": "#/$defs/id" }, "messageItemId": { "$ref": "#/$defs/id" }, "label": { "$ref": "#/$defs/shortText" }, "available": { "type": "boolean" }, "reference": { "type": ["string", "null"], "maxLength": 4096 } },
+      "additionalProperties": false
+    },
+    "safetyReview": {
+      "type": "object",
+      "required": ["schema", "reviewId", "targetExecutionId", "status", "decision", "summary"],
+      "properties": { "schema": { "const": "paperclip.safety.review.v1" }, "reviewId": { "$ref": "#/$defs/id" }, "targetExecutionId": { "anyOf": [{ "$ref": "#/$defs/id" }, { "type": "null" }] }, "status": { "enum": ["running", "completed", "failed"] }, "decision": { "enum": ["pending", "allowed", "denied", "user_required", "unknown"] }, "summary": { "$ref": "#/$defs/nullableShortText" } },
+      "additionalProperties": false
+    },
+    "terminalInput": {
+      "type": "object",
+      "required": ["schema", "executionId", "origin", "inputClass", "byteCount"],
+      "properties": { "schema": { "const": "paperclip.terminal.input_sent.v1" }, "executionId": { "$ref": "#/$defs/id" }, "origin": { "enum": ["agent", "user", "system"] }, "inputClass": { "enum": ["text", "control", "eof"] }, "byteCount": { "type": "integer", "minimum": 0 } },
+      "additionalProperties": false
+    },
+    "wait": {
+      "type": "object",
+      "required": ["schema", "waitId", "reason", "status", "plannedDurationMs", "elapsedDurationMs"],
+      "properties": { "schema": { "const": "paperclip.wait.v1" }, "waitId": { "$ref": "#/$defs/id" }, "reason": { "enum": ["timer", "provider", "rate_limit", "unknown"] }, "status": { "enum": ["running", "completed", "interrupted", "cancelled"] }, "plannedDurationMs": { "type": ["integer", "null"], "minimum": 0 }, "elapsedDurationMs": { "type": ["integer", "null"], "minimum": 0 } },
+      "additionalProperties": false
+    },
+    "providerNotice": {
+      "type": "object",
+      "required": ["schema", "noticeId", "severity", "category", "scope", "recoverable", "userActionable", "summary"],
+      "properties": { "schema": { "const": "paperclip.provider.notice.v1" }, "noticeId": { "$ref": "#/$defs/id" }, "severity": { "enum": ["info", "warning", "error"] }, "category": { "type": "string", "minLength": 1, "maxLength": 160 }, "scope": { "enum": ["turn", "session", "environment", "account"] }, "recoverable": { "type": "boolean" }, "userActionable": { "type": "boolean" }, "summary": { "$ref": "#/$defs/shortText" } },
+      "additionalProperties": false
+    }
+  }
+}
diff --git a/packages/paperclip-runner/protocol/schemas/question-adapter-fixture.schema.json b/packages/paperclip-runner/protocol/schemas/question-adapter-fixture.schema.json
new file mode 100644
index 0000000000..04715dd336
--- /dev/null
+++ b/packages/paperclip-runner/protocol/schemas/question-adapter-fixture.schema.json
@@ -0,0 +1,16 @@
+{
+  "$schema": "https://json-schema.org/draft/2020-12/schema",
+  "$id": "https://paperclip.dev/schemas/prp/v1/question-adapter-fixture.schema.json",
+  "title": "Harness question adapter conformance fixture",
+  "type": "object",
+  "required": ["schema", "adapter", "nativeRequest", "canonicalQuestionSet", "canonicalResponse", "nativeResponse"],
+  "properties": {
+    "schema": { "const": "paperclip.question_adapter_fixture.v1" },
+    "adapter": { "type": "string", "minLength": 1, "maxLength": 160 },
+    "nativeRequest": {},
+    "canonicalQuestionSet": { "$ref": "https://paperclip.dev/schemas/prp/v1/question-set.schema.json" },
+    "canonicalResponse": { "$ref": "https://paperclip.dev/schemas/prp/v1/question-response.schema.json" },
+    "nativeResponse": {}
+  },
+  "additionalProperties": false
+}
diff --git a/packages/paperclip-runner/protocol/schemas/question-response.schema.json b/packages/paperclip-runner/protocol/schemas/question-response.schema.json
new file mode 100644
index 0000000000..f089054853
--- /dev/null
+++ b/packages/paperclip-runner/protocol/schemas/question-response.schema.json
@@ -0,0 +1,28 @@
+{
+  "$schema": "https://json-schema.org/draft/2020-12/schema",
+  "$id": "https://paperclip.dev/schemas/prp/v1/question-response.schema.json",
+  "title": "Paperclip question response",
+  "type": "object",
+  "required": ["schema", "answers"],
+  "properties": {
+    "schema": { "const": "paperclip.question_response.v1" },
+    "answers": {
+      "type": "object",
+      "propertyNames": { "minLength": 1, "maxLength": 160 },
+      "additionalProperties": {
+        "type": "object",
+        "properties": {
+          "selectedOptionIds": {
+            "type": "array",
+            "uniqueItems": true,
+            "items": { "type": "string", "minLength": 1, "maxLength": 160 }
+          },
+          "text": { "type": "string", "maxLength": 100000 },
+          "customText": { "type": "string", "maxLength": 100000 }
+        },
+        "additionalProperties": false
+      }
+    }
+  },
+  "additionalProperties": false
+}
diff --git a/packages/paperclip-runner/protocol/schemas/question-set.schema.json b/packages/paperclip-runner/protocol/schemas/question-set.schema.json
new file mode 100644
index 0000000000..995bfa8f72
--- /dev/null
+++ b/packages/paperclip-runner/protocol/schemas/question-set.schema.json
@@ -0,0 +1,90 @@
+{
+  "$schema": "https://json-schema.org/draft/2020-12/schema",
+  "$id": "https://paperclip.dev/schemas/prp/v1/question-set.schema.json",
+  "title": "Paperclip question set",
+  "type": "object",
+  "required": ["schema", "questions"],
+  "properties": {
+    "schema": { "const": "paperclip.question_set.v1" },
+    "title": { "type": "string", "maxLength": 1000 },
+    "description": { "type": "string", "maxLength": 4000 },
+    "submitLabel": { "type": "string", "maxLength": 200 },
+    "questions": {
+      "type": "array",
+      "minItems": 1,
+      "maxItems": 64,
+      "items": { "$ref": "#/$defs/question" }
+    }
+  },
+  "$defs": {
+    "option": {
+      "type": "object",
+      "required": ["id", "label"],
+      "properties": {
+        "id": { "type": "string", "minLength": 1, "maxLength": 160 },
+        "label": { "type": "string", "minLength": 1, "maxLength": 1000 },
+        "description": { "type": "string", "maxLength": 4000 }
+      },
+      "additionalProperties": false
+    },
+    "customAnswer": {
+      "type": "object",
+      "required": ["enabled"],
+      "properties": {
+        "enabled": { "const": true },
+        "label": { "type": "string", "maxLength": 1000 },
+        "placeholder": { "type": "string", "maxLength": 1000 }
+      },
+      "additionalProperties": false
+    },
+    "textValidation": {
+      "type": "object",
+      "properties": {
+        "minLength": { "type": "integer", "minimum": 0, "maximum": 100000 },
+        "maxLength": { "type": "integer", "minimum": 0, "maximum": 100000 },
+        "pattern": { "type": "string", "maxLength": 1000 },
+        "inputType": { "enum": ["text", "number", "integer"] },
+        "minimum": { "type": "number" },
+        "maximum": { "type": "number" }
+      },
+      "additionalProperties": false
+    },
+    "question": {
+      "type": "object",
+      "required": ["id", "prompt", "required", "answerMode"],
+      "properties": {
+        "id": { "type": "string", "minLength": 1, "maxLength": 160 },
+        "header": { "type": "string", "maxLength": 1000 },
+        "prompt": { "type": "string", "minLength": 1, "maxLength": 4000 },
+        "helpText": { "type": "string", "maxLength": 4000 },
+        "required": { "type": "boolean" },
+        "answerMode": { "enum": ["single_select", "multi_select", "text"] },
+        "options": {
+          "type": "array",
+          "maxItems": 128,
+          "items": { "$ref": "#/$defs/option" }
+        },
+        "customAnswer": { "$ref": "#/$defs/customAnswer" },
+        "textValidation": { "$ref": "#/$defs/textValidation" }
+      },
+      "allOf": [
+        {
+          "if": { "properties": { "answerMode": { "const": "text" } }, "required": ["answerMode"] },
+          "then": {
+            "properties": { "options": { "type": "array", "maxItems": 0 } },
+            "not": { "required": ["customAnswer"] }
+          }
+        },
+        {
+          "if": { "properties": { "answerMode": { "enum": ["single_select", "multi_select"] } }, "required": ["answerMode"] },
+          "then": {
+            "required": ["options"],
+            "properties": { "options": { "type": "array", "minItems": 1 } }
+          }
+        }
+      ],
+      "additionalProperties": false
+    }
+  },
+  "additionalProperties": false
+}
diff --git a/packages/paperclip-runner/protocol/schemas/request.schema.json b/packages/paperclip-runner/protocol/schemas/request.schema.json
new file mode 100644
index 0000000000..78441bc7bf
--- /dev/null
+++ b/packages/paperclip-runner/protocol/schemas/request.schema.json
@@ -0,0 +1,79 @@
+{
+  "$schema": "https://json-schema.org/draft/2020-12/schema",
+  "$id": "https://paperclip.dev/schemas/prp/v1/request.schema.json",
+  "title": "PRP request",
+  "oneOf": [
+    {
+      "type": "object",
+      "required": ["schema", "requestKind", "requestId", "type", "status", "prompt", "input"],
+      "properties": {
+        "schema": { "const": "paperclip.runtime_request.v2" },
+        "requestKind": { "const": "runtime" },
+        "requestId": { "type": "string", "minLength": 1, "maxLength": 160 },
+        "type": { "const": "input" },
+        "status": { "enum": ["pending", "resolved", "expired", "cancelled"] },
+        "prompt": { "type": "string", "minLength": 1, "maxLength": 4000 },
+        "input": { "$ref": "https://paperclip.dev/schemas/prp/v1/question-set.schema.json" },
+        "origin": {
+          "type": "object",
+          "required": ["adapter"],
+          "properties": {
+            "adapter": { "type": "string", "minLength": 1, "maxLength": 160 },
+            "provider": { "type": "string", "minLength": 1, "maxLength": 160 },
+            "method": { "type": "string", "minLength": 1, "maxLength": 500 }
+          },
+          "additionalProperties": false
+        },
+        "turnId": { "type": "string", "minLength": 1, "maxLength": 160 },
+        "itemId": { "type": "string", "minLength": 1, "maxLength": 160 }
+      },
+      "additionalProperties": false
+    },
+    {
+      "type": "object",
+      "required": ["schema", "requestKind", "requestId", "type", "status", "prompt"],
+      "properties": {
+        "schema": { "const": "paperclip.runtime_request.v1" },
+        "requestKind": { "const": "runtime" },
+        "requestId": { "type": "string", "minLength": 1, "maxLength": 160 },
+        "type": { "enum": ["permission", "input"] },
+        "status": { "enum": ["pending", "resolved", "expired", "cancelled"] },
+        "prompt": { "type": "string", "minLength": 1, "maxLength": 4000 },
+        "choices": {
+          "type": "array",
+          "items": {
+            "type": "object",
+            "required": ["key", "label"],
+            "properties": {
+              "key": { "type": "string", "minLength": 1 },
+              "label": { "type": "string", "minLength": 1 }
+            },
+            "additionalProperties": true
+          }
+        }
+      },
+      "additionalProperties": true
+    },
+    {
+      "type": "object",
+      "required": ["schema", "requestKind", "requestId", "kind", "blocking", "payload"],
+      "properties": {
+        "schema": { "const": "paperclip.interaction_request.v1" },
+        "requestKind": { "const": "issue_thread" },
+        "requestId": { "type": "string", "minLength": 1, "maxLength": 160 },
+        "kind": {
+          "enum": [
+            "request_confirmation",
+            "request_checkbox_confirmation",
+            "request_item_verdicts",
+            "ask_user_questions",
+            "suggest_tasks"
+          ]
+        },
+        "blocking": { "type": "boolean" },
+        "payload": { "type": "object", "additionalProperties": true }
+      },
+      "additionalProperties": true
+    }
+  ]
+}
diff --git a/packages/paperclip-runner/protocol/schemas/result.schema.json b/packages/paperclip-runner/protocol/schemas/result.schema.json
new file mode 100644
index 0000000000..62983b280e
--- /dev/null
+++ b/packages/paperclip-runner/protocol/schemas/result.schema.json
@@ -0,0 +1,151 @@
+{
+  "$schema": "https://json-schema.org/draft/2020-12/schema",
+  "$id": "https://paperclip.dev/schemas/prp/v1/result.schema.json",
+  "title": "PRP structured run result",
+  "type": "object",
+  "required": [
+    "schema",
+    "reportedWorkDisposition",
+    "summary",
+    "completionClaim",
+    "evidence",
+    "verification",
+    "attentionRequests",
+    "artifacts"
+  ],
+  "properties": {
+    "schema": { "const": "paperclip.run_result.v1" },
+    "reportedWorkDisposition": {
+      "enum": ["done", "blocked", "needs_review", "yielded"]
+    },
+    "summary": { "type": "string", "minLength": 1, "maxLength": 12000 },
+    "completionClaim": {
+      "type": "object",
+      "required": ["contractRevision", "objectiveSatisfied", "criteria", "remainingWork"],
+      "properties": {
+        "contractRevision": { "type": "string", "minLength": 1 },
+        "objectiveSatisfied": { "type": "boolean" },
+        "criteria": {
+          "type": "array",
+          "items": {
+            "type": "object",
+            "required": ["criterionId", "status", "evidenceRefs"],
+            "properties": {
+              "criterionId": { "type": "string", "minLength": 1 },
+              "status": { "enum": ["satisfied", "not_satisfied", "unknown"] },
+              "evidenceRefs": { "type": "array", "items": { "type": "string" } },
+              "explanation": { "type": "string" }
+            },
+            "additionalProperties": true
+          }
+        },
+        "remainingWork": {
+          "type": "array",
+          "items": {
+            "type": "object",
+            "required": ["description", "blocksCompletion"],
+            "properties": {
+              "description": { "type": "string", "minLength": 1 },
+              "blocksCompletion": { "type": "boolean" }
+            },
+            "additionalProperties": true
+          }
+        }
+      },
+      "additionalProperties": true
+    },
+    "evidence": { "type": "array", "items": { "type": "object" } },
+    "verification": {
+      "type": "array",
+      "description": "Checks used to verify the work. Use failed only when the check actually ran and found a defect in the work. If a check could not run or complete because the environment, tool, dependency, permission, credential, policy, external service, or budget was unavailable, use not_run with reasonCode even when the attempted command exited non-zero.",
+      "items": {
+        "type": "object",
+        "required": ["commandOrCheck", "status"],
+        "properties": {
+          "commandOrCheck": { "type": "string", "minLength": 1 },
+          "status": {
+            "enum": ["passed", "failed", "not_run"],
+            "description": "passed means the check ran and succeeded; failed means it ran to a meaningful verdict and found the work incorrect; not_run means no meaningful verdict was possible because the check was not attempted or could not complete."
+          },
+          "reasonCode": {
+            "description": "Required for not_run; identify why the check had no meaningful verdict.",
+            "enum": [
+              "environment_unavailable",
+              "tool_unavailable",
+              "dependency_missing",
+              "permission_denied",
+              "credential_missing",
+              "policy_restricted",
+              "external_service_unavailable",
+              "budget_exhausted",
+              "other"
+            ]
+          },
+          "detail": { "type": "string" },
+          "artifactRef": { "type": "string" }
+        },
+        "additionalProperties": true
+      }
+    },
+    "blocker": {
+      "type": "object",
+      "required": ["reasonCode", "owner", "unblockAction", "scope"],
+      "properties": {
+        "reasonCode": { "type": "string", "minLength": 1 },
+        "owner": { "type": "object", "additionalProperties": true },
+        "unblockAction": { "type": "string", "minLength": 1 },
+        "scope": { "enum": ["current_track", "task_wide"] }
+      },
+      "additionalProperties": true
+    },
+    "attentionRequests": {
+      "type": "array",
+      "items": {
+        "type": "object",
+        "properties": {
+          "kind": { "type": "string", "minLength": 1 },
+          "summary": { "type": "string", "minLength": 1 },
+          "ownerClass": { "enum": ["human", "agent", "external_system"] },
+          "targetAgentId": { "type": "string", "minLength": 1 }
+        },
+        "additionalProperties": true
+      }
+    },
+    "artifacts": {
+      "type": "array",
+      "items": {
+        "type": "object",
+        "required": ["kind", "ref"],
+        "properties": {
+          "kind": { "type": "string", "minLength": 1 },
+          "ref": { "type": "string", "minLength": 1 },
+          "title": { "type": "string" }
+        },
+        "additionalProperties": true
+      }
+    },
+    "continuation": {
+      "type": "object",
+      "required": ["kind", "summary", "idempotencyKey"],
+      "properties": {
+        "kind": {
+          "enum": ["same_agent", "retry", "delegated_issue", "response_wake", "monitor"]
+        },
+        "summary": { "type": "string", "minLength": 1 },
+        "idempotencyKey": { "type": "string", "minLength": 1 }
+      },
+      "additionalProperties": true
+    }
+  },
+  "allOf": [
+    {
+      "if": { "properties": { "reportedWorkDisposition": { "const": "blocked" } } },
+      "then": { "required": ["blocker"] }
+    },
+    {
+      "if": { "properties": { "reportedWorkDisposition": { "const": "yielded" } } },
+      "then": { "required": ["continuation"] }
+    }
+  ],
+  "additionalProperties": true
+}
diff --git a/packages/paperclip-runner/protocol/schemas/semantic-tool.schema.json b/packages/paperclip-runner/protocol/schemas/semantic-tool.schema.json
new file mode 100644
index 0000000000..657a7e4e9f
--- /dev/null
+++ b/packages/paperclip-runner/protocol/schemas/semantic-tool.schema.json
@@ -0,0 +1,164 @@
+{
+  "$schema": "https://json-schema.org/draft/2020-12/schema",
+  "$id": "https://paperclip.dev/schemas/prp/v1/semantic-tool.schema.json",
+  "title": "PRP provider-neutral semantic tool envelope",
+  "type": "object",
+  "required": [
+    "schema",
+    "schemaVersion",
+    "phase",
+    "operationId",
+    "callId",
+    "correlation",
+    "idempotencyKey",
+    "content"
+  ],
+  "properties": {
+    "schema": { "const": "paperclip.prp.semantic_tool.v1" },
+    "schemaVersion": { "const": 1 },
+    "phase": { "enum": ["input", "result"] },
+    "operationId": { "$ref": "#/$defs/stableId" },
+    "callId": { "$ref": "#/$defs/stableId" },
+    "correlation": {
+      "type": "object",
+      "required": ["runId", "normalizedSessionId", "turnId", "itemId"],
+      "properties": {
+        "runId": { "$ref": "#/$defs/stableId" },
+        "normalizedSessionId": { "$ref": "#/$defs/stableId" },
+        "turnId": { "$ref": "#/$defs/stableId" },
+        "itemId": { "$ref": "#/$defs/stableId" },
+        "requestId": { "$ref": "#/$defs/stableId" }
+      },
+      "additionalProperties": true
+    },
+    "idempotencyKey": {
+      "type": ["string", "null"],
+      "minLength": 1,
+      "maxLength": 240
+    },
+    "content": { "$ref": "#/$defs/safeContent" },
+    "outcome": {
+      "enum": ["succeeded", "denied", "conflict", "duplicate", "unavailable", "failed"]
+    },
+    "code": { "$ref": "#/$defs/stableCode" },
+    "retryable": { "type": "boolean" },
+    "authorizationBoundary": {
+      "enum": ["company", "actor", "active_task", "grant", "governed_action", "lock", "revision"]
+    },
+    "operationReceiptId": { "$ref": "#/$defs/stableId" },
+    "auditReceiptId": { "$ref": "#/$defs/stableId" },
+    "currentRevision": {
+      "oneOf": [
+        { "type": "integer", "minimum": 0 },
+        { "$ref": "#/$defs/stableId" }
+      ]
+    },
+    "duplicateOfReceiptId": { "$ref": "#/$defs/stableId" },
+    "artifactRefs": {
+      "type": "array",
+      "items": {
+        "allOf": [
+          { "$ref": "#/$defs/safeReference" },
+          {
+            "type": "object",
+            "properties": { "kind": { "enum": ["artifact", "work_product"] } }
+          }
+        ]
+      },
+      "uniqueItems": true
+    },
+    "targets": {
+      "type": "array",
+      "items": { "$ref": "#/$defs/immutableTarget" },
+      "uniqueItems": true
+    },
+    "causalRefs": {
+      "type": "array",
+      "items": { "$ref": "#/$defs/safeReference" },
+      "uniqueItems": true
+    }
+  },
+  "allOf": [
+    {
+      "if": { "properties": { "phase": { "const": "result" } } },
+      "then": {
+        "required": [
+          "outcome",
+          "code",
+          "retryable",
+          "authorizationBoundary",
+          "operationReceiptId"
+        ]
+      }
+    }
+  ],
+  "additionalProperties": true,
+  "$defs": {
+    "stableId": {
+      "type": "string",
+      "minLength": 1,
+      "maxLength": 240,
+      "pattern": "^[A-Za-z0-9][A-Za-z0-9._:-]*$"
+    },
+    "stableCode": {
+      "type": "string",
+      "minLength": 1,
+      "maxLength": 160,
+      "pattern": "^[a-z][a-z0-9_.:-]*$"
+    },
+    "safeContent": {
+      "type": "object",
+      "required": ["digest", "redactionDisposition", "references"],
+      "properties": {
+        "digest": {
+          "type": "string",
+          "pattern": "^sha256:[a-f0-9]{64}$"
+        },
+        "redactionDisposition": {
+          "enum": ["digest_only", "allowlisted_references", "redacted"]
+        },
+        "references": {
+          "type": "array",
+          "items": { "$ref": "#/$defs/safeReference" },
+          "uniqueItems": true
+        }
+      },
+      "additionalProperties": true
+    },
+    "safeReference": {
+      "type": "object",
+      "required": ["kind", "id"],
+      "properties": {
+        "kind": {
+          "enum": [
+            "task",
+            "document_revision",
+            "interaction",
+            "approval",
+            "decision",
+            "artifact",
+            "work_product",
+            "wake",
+            "monitor",
+            "audit",
+            "operation"
+          ]
+        },
+        "id": { "$ref": "#/$defs/stableId" }
+      },
+      "additionalProperties": true
+    },
+    "immutableTarget": {
+      "type": "object",
+      "required": ["kind", "id", "immutable"],
+      "properties": {
+        "kind": { "enum": ["document_revision", "interaction", "approval", "decision"] },
+        "id": { "$ref": "#/$defs/stableId" },
+        "immutable": { "const": true },
+        "revisionId": { "$ref": "#/$defs/stableId" },
+        "decisionId": { "$ref": "#/$defs/stableId" }
+      },
+      "additionalProperties": true
+    }
+  }
+}
diff --git a/packages/paperclip-runner/protocol/schemas/stop-reason.schema.json b/packages/paperclip-runner/protocol/schemas/stop-reason.schema.json
new file mode 100644
index 0000000000..183615f559
--- /dev/null
+++ b/packages/paperclip-runner/protocol/schemas/stop-reason.schema.json
@@ -0,0 +1,65 @@
+{
+  "$schema": "https://json-schema.org/draft/2020-12/schema",
+  "$id": "https://paperclip.dev/schemas/prp/v1/stop-reason.schema.json",
+  "title": "PRP terminal stop reason receipt",
+  "type": "object",
+  "required": [
+    "schema",
+    "schemaVersion",
+    "receiptId",
+    "kind",
+    "code",
+    "retryable",
+    "decisionId",
+    "limitClass",
+    "aggregate"
+  ],
+  "properties": {
+    "schema": { "const": "paperclip.prp.stop_reason.v1" },
+    "schemaVersion": { "const": 1 },
+    "receiptId": { "$ref": "#/$defs/stableId" },
+    "kind": { "enum": ["budget", "cost"] },
+    "code": {
+      "type": "string",
+      "minLength": 1,
+      "maxLength": 160,
+      "pattern": "^[a-z][a-z0-9_.:-]*$"
+    },
+    "retryable": { "type": "boolean" },
+    "decisionId": { "$ref": "#/$defs/stableId" },
+    "limitClass": {
+      "enum": [
+        "company_monthly",
+        "actor_monthly",
+        "project_monthly",
+        "run_cost",
+        "provider_quota"
+      ]
+    },
+    "aggregate": {
+      "type": "object",
+      "required": ["unit", "observed", "limit", "window"],
+      "properties": {
+        "unit": { "enum": ["cents", "usd_micros", "tokens"] },
+        "observed": { "type": "integer", "minimum": 0 },
+        "limit": { "type": "integer", "minimum": 0 },
+        "window": { "enum": ["run", "monthly_utc", "provider_window"] }
+      },
+      "additionalProperties": true
+    },
+    "relatedReceiptIds": {
+      "type": "array",
+      "items": { "$ref": "#/$defs/stableId" },
+      "uniqueItems": true
+    }
+  },
+  "additionalProperties": true,
+  "$defs": {
+    "stableId": {
+      "type": "string",
+      "minLength": 1,
+      "maxLength": 240,
+      "pattern": "^[A-Za-z0-9][A-Za-z0-9._:-]*$"
+    }
+  }
+}
diff --git a/packages/paperclip-runner/protocol/schemas/terminal.schema.json b/packages/paperclip-runner/protocol/schemas/terminal.schema.json
new file mode 100644
index 0000000000..3538d20120
--- /dev/null
+++ b/packages/paperclip-runner/protocol/schemas/terminal.schema.json
@@ -0,0 +1,26 @@
+{
+  "$schema": "https://json-schema.org/draft/2020-12/schema",
+  "$id": "https://paperclip.dev/schemas/prp/v1/terminal.schema.json",
+  "title": "PRP run terminal state",
+  "type": "object",
+  "required": [
+    "schema",
+    "turnTerminalState",
+    "runTerminalState",
+    "reportedWorkDisposition"
+  ],
+  "properties": {
+    "schema": { "const": "paperclip.prp.terminal.v1" },
+    "turnTerminalState": {
+      "enum": ["completed", "failed", "interrupted", "cancelled"]
+    },
+    "runTerminalState": { "enum": ["succeeded", "failed", "cancelled"] },
+    "reportedWorkDisposition": {
+      "enum": ["done", "blocked", "needs_review", "yielded"]
+    },
+    "workAssessmentId": { "type": "string", "minLength": 1 },
+    "statusDecisionId": { "type": "string", "minLength": 1 },
+    "stopReason": { "$ref": "https://paperclip.dev/schemas/prp/v1/stop-reason.schema.json" }
+  },
+  "additionalProperties": true
+}
diff --git a/packages/paperclip-runner/protocol/schemas/usage.schema.json b/packages/paperclip-runner/protocol/schemas/usage.schema.json
new file mode 100644
index 0000000000..68c912f2dc
--- /dev/null
+++ b/packages/paperclip-runner/protocol/schemas/usage.schema.json
@@ -0,0 +1,32 @@
+{
+  "$schema": "https://json-schema.org/draft/2020-12/schema",
+  "$id": "https://paperclip.dev/schemas/prp/v1/usage.schema.json",
+  "title": "PRP provider usage receipt",
+  "type": "object",
+  "required": ["provider", "model", "cumulative", "runDelta"],
+  "properties": {
+    "provider": { "type": "string", "minLength": 1, "maxLength": 80 },
+    "model": { "type": ["string", "null"], "maxLength": 240 },
+    "providerSessionId": { "type": ["string", "null"], "maxLength": 240 },
+    "providerRequestId": { "type": ["string", "null"], "maxLength": 240 },
+    "cumulative": { "$ref": "#/$defs/measurement" },
+    "runDelta": { "$ref": "#/$defs/measurement" }
+  },
+  "additionalProperties": false,
+  "$defs": {
+    "measurement": {
+      "type": "object",
+      "required": ["inputTokens", "outputTokens", "cacheReadTokens", "cacheWriteTokens", "activeSeconds", "requests", "providerCostUsd"],
+      "properties": {
+        "inputTokens": { "type": "integer", "minimum": 0 },
+        "outputTokens": { "type": "integer", "minimum": 0 },
+        "cacheReadTokens": { "type": "integer", "minimum": 0 },
+        "cacheWriteTokens": { "type": "integer", "minimum": 0 },
+        "activeSeconds": { "type": "number", "minimum": 0 },
+        "requests": { "type": "integer", "minimum": 0 },
+        "providerCostUsd": { "type": "number", "minimum": 0 }
+      },
+      "additionalProperties": false
+    }
+  }
+}
diff --git a/packages/paperclip-runner/protocol/schemas/workspace-diff.schema.json b/packages/paperclip-runner/protocol/schemas/workspace-diff.schema.json
new file mode 100644
index 0000000000..ebf317dbae
--- /dev/null
+++ b/packages/paperclip-runner/protocol/schemas/workspace-diff.schema.json
@@ -0,0 +1,49 @@
+{
+  "$schema": "https://json-schema.org/draft/2020-12/schema",
+  "$id": "https://paperclip.dev/schemas/prp/v1/workspace-diff.schema.json",
+  "title": "Paperclip workspace diff",
+  "type": "object",
+  "required": ["schema", "changeSetId", "revision", "source", "complete", "files", "totals", "patchArtifactRef"],
+  "properties": {
+    "schema": { "const": "paperclip.workspace.diff.v1" },
+    "changeSetId": { "type": "string", "minLength": 1, "maxLength": 200 },
+    "revision": { "type": "integer", "minimum": 1 },
+    "source": { "enum": ["harness_reported", "runner_verified"] },
+    "complete": { "type": "boolean" },
+    "files": {
+      "type": "array",
+      "maxItems": 2000,
+      "items": {
+        "type": "object",
+        "required": ["path", "operation", "previousPath", "additions", "deletions", "binary", "diff"],
+        "properties": {
+          "path": { "type": "string", "minLength": 1, "maxLength": 1024, "pattern": "^(?!/)(?!.*(?:^|/)\\.\\.(?:/|$)).+$" },
+          "operation": { "enum": ["create", "modify", "delete", "rename", "mode_change"] },
+          "previousPath": {
+            "oneOf": [
+              { "type": "null" },
+              { "type": "string", "minLength": 1, "maxLength": 1024, "pattern": "^(?!/)(?!.*(?:^|/)\\.\\.(?:/|$)).+$" }
+            ]
+          },
+          "additions": { "type": ["integer", "null"], "minimum": 0 },
+          "deletions": { "type": ["integer", "null"], "minimum": 0 },
+          "binary": { "type": "boolean" },
+          "diff": { "type": ["string", "null"], "maxLength": 262144 }
+        },
+        "additionalProperties": false
+      }
+    },
+    "totals": {
+      "type": "object",
+      "required": ["files", "additions", "deletions"],
+      "properties": {
+        "files": { "type": "integer", "minimum": 0 },
+        "additions": { "type": ["integer", "null"], "minimum": 0 },
+        "deletions": { "type": ["integer", "null"], "minimum": 0 }
+      },
+      "additionalProperties": false
+    },
+    "patchArtifactRef": { "type": ["string", "null"], "maxLength": 2048 }
+  },
+  "additionalProperties": false
+}
diff --git a/packages/paperclip-runner/protocol/schemas/workspace-file-reference.schema.json b/packages/paperclip-runner/protocol/schemas/workspace-file-reference.schema.json
new file mode 100644
index 0000000000..e0dc8555d2
--- /dev/null
+++ b/packages/paperclip-runner/protocol/schemas/workspace-file-reference.schema.json
@@ -0,0 +1,26 @@
+{
+  "$schema": "https://json-schema.org/draft/2020-12/schema",
+  "$id": "https://paperclip.dev/schemas/prp/v1/workspace-file-reference.schema.json",
+  "title": "Paperclip workspace file reference",
+  "type": "object",
+  "required": ["schema", "referenceId", "source", "path", "displayName", "mediaType", "presentation", "line", "preview", "previewTruncated", "contentDigest"],
+  "properties": {
+    "schema": { "const": "paperclip.workspace.file_reference.v1" },
+    "referenceId": { "type": "string", "minLength": 1, "maxLength": 240 },
+    "source": { "enum": ["harness_reported", "runner_verified"] },
+    "path": { "type": "string", "minLength": 1, "maxLength": 1024, "pattern": "^(?!/)(?!.*(?:^|/)\\.\\.(?:/|$)).+$" },
+    "displayName": { "type": "string", "minLength": 1, "maxLength": 255 },
+    "mediaType": { "type": ["string", "null"], "maxLength": 160 },
+    "presentation": { "enum": ["document", "code", "image", "generic"] },
+    "line": { "type": ["integer", "null"], "minimum": 1 },
+    "preview": { "type": ["string", "null"], "maxLength": 262144 },
+    "previewTruncated": { "type": "boolean" },
+    "contentDigest": {
+      "oneOf": [
+        { "type": "null" },
+        { "type": "string", "pattern": "^sha256:[a-f0-9]{64}$" }
+      ]
+    }
+  },
+  "additionalProperties": false
+}
diff --git a/packages/paperclip-runner/scripts/generate-protocol-manifest.mjs b/packages/paperclip-runner/scripts/generate-protocol-manifest.mjs
new file mode 100644
index 0000000000..3bc3d59462
--- /dev/null
+++ b/packages/paperclip-runner/scripts/generate-protocol-manifest.mjs
@@ -0,0 +1,114 @@
+import { readFile, writeFile } from "node:fs/promises";
+import { dirname, resolve } from "node:path";
+import { fileURLToPath } from "node:url";
+
+import {
+  SUPPORTED_FIXTURE_VERSION,
+  SUPPORTED_PROTOCOL_VERSION,
+  assertCodexQuestionFixture,
+  assertConformanceFixturePair,
+  assertReplayFixtureCompatibility,
+  assertSchemaInstance,
+  compileProtocolValidators,
+  listJsonFiles,
+  loadSchemaCatalog,
+  portableRelative,
+  readJson,
+  sha256,
+} from "./protocol-contract.mjs";
+
+const packageRoot = resolve(dirname(fileURLToPath(import.meta.url)), "..");
+const protocolRoot = resolve(packageRoot, "protocol");
+const schemaDirectory = resolve(protocolRoot, "schemas");
+const fixtureDirectory = resolve(protocolRoot, "fixtures");
+const outputPath = resolve(protocolRoot, "manifest.json");
+const expectedRejectedFixture = "fixtures/replay/unsupported-required-version.json";
+
+export async function buildProtocolManifest() {
+  const schemas = await loadSchemaCatalog(schemaDirectory);
+  const validators = compileProtocolValidators(schemas);
+  const fixtureFiles = await listJsonFiles(fixtureDirectory);
+  const fixtures = [];
+  const fixtureValues = new Map();
+
+  for (const path of fixtureFiles) {
+    const relativePath = portableRelative(protocolRoot, path);
+    const { source, value } = await readJson(path);
+    fixtureValues.set(relativePath, value);
+    let expectation = "accept";
+    let compatibilityCase = "canonical";
+
+    if (relativePath.startsWith("fixtures/replay/")) {
+      if (relativePath === expectedRejectedFixture) {
+        expectation = "reject";
+        compatibilityCase = "unknown-required-version";
+        try {
+          assertReplayFixtureCompatibility(value);
+          throw new Error(`${relativePath} did not fail closed`);
+        } catch (error) {
+          if (!String(error.message).startsWith("unsupported_required_version:")) throw error;
+        }
+        assertSchemaInstance(validators.fixture, value, relativePath, false);
+      } else {
+        assertReplayFixtureCompatibility(value);
+        assertSchemaInstance(validators.fixture, value, relativePath);
+        if (relativePath.endsWith("unknown-optional-fields.json")) {
+          compatibilityCase = "additive-optional-fields";
+        }
+      }
+    } else if (relativePath === "fixtures/questions/codex.json") {
+      assertCodexQuestionFixture(value);
+      assertSchemaInstance(validators.questionAdapterFixture, value, relativePath);
+      compatibilityCase = "codex-structured-input";
+    } else if (relativePath === "fixtures/conformance-minimal-run.json") {
+      assertSchemaInstance(validators.conformanceFixture, value, relativePath);
+      compatibilityCase = "cross-language-input";
+    } else if (relativePath === "fixtures/conformance-expected-output.json") {
+      assertSchemaInstance(validators.conformanceOutput, value, relativePath);
+      compatibilityCase = "cross-language-output";
+    }
+
+    fixtures.push({
+      path: relativePath,
+      sha256: sha256(source),
+      expectation,
+      compatibilityCase,
+    });
+  }
+
+  assertConformanceFixturePair(
+    fixtureValues.get("fixtures/conformance-minimal-run.json"),
+    fixtureValues.get("fixtures/conformance-expected-output.json"),
+  );
+
+  return {
+    schema: "paperclip.prp.contract_manifest.v1",
+    protocolVersion: SUPPORTED_PROTOCOL_VERSION,
+    fixtureVersion: SUPPORTED_FIXTURE_VERSION,
+    generatedFrom: ["protocol/schemas", "protocol/fixtures"],
+    schemas: schemas.map((record) => ({
+      path: portableRelative(protocolRoot, record.path),
+      id: record.value.$id,
+      sha256: sha256(record.source),
+    })),
+    fixtures,
+  };
+}
+
+async function main() {
+  const encoded = `${JSON.stringify(await buildProtocolManifest(), null, 2)}\n`;
+  if (process.argv.includes("--check")) {
+    const current = await readFile(outputPath, "utf8").catch(() => "");
+    if (current !== encoded) {
+      process.stderr.write("The generated PRP contract manifest is stale. Run pnpm generate:protocol-manifest.\n");
+      process.exitCode = 1;
+    } else {
+      process.stdout.write("The generated PRP contract manifest matches its sources.\n");
+    }
+  } else {
+    await writeFile(outputPath, encoded);
+    process.stdout.write(`Wrote ${outputPath}\n`);
+  }
+}
+
+if (resolve(process.argv[1] ?? "") === fileURLToPath(import.meta.url)) await main();
diff --git a/packages/paperclip-runner/scripts/protocol-contract.mjs b/packages/paperclip-runner/scripts/protocol-contract.mjs
new file mode 100644
index 0000000000..35743d4c7d
--- /dev/null
+++ b/packages/paperclip-runner/scripts/protocol-contract.mjs
@@ -0,0 +1,243 @@
+import { createHash } from "node:crypto";
+import { readdir, readFile } from "node:fs/promises";
+import { relative, resolve, sep } from "node:path";
+
+import Ajv2020 from "ajv/dist/2020.js";
+
+export const JSON_SCHEMA_DIALECT = "https://json-schema.org/draft/2020-12/schema";
+export const PRP_SCHEMA_ID_PREFIX = "https://paperclip.dev/schemas/prp/v1/";
+export const SUPPORTED_FIXTURE_VERSION = 1;
+export const SUPPORTED_PROTOCOL_VERSION = 1;
+export const SUPPORTED_EVENT_SCHEMA_VERSION = 1;
+
+function contractError(code, detail) {
+  return new Error(`${code}: ${detail}`);
+}
+
+export async function readJson(path) {
+  const source = await readFile(path, "utf8");
+  try {
+    return { source, value: JSON.parse(source) };
+  } catch (error) {
+    throw contractError("invalid_json", `${path}: ${error.message}`);
+  }
+}
+
+export async function listJsonFiles(root) {
+  const entries = await readdir(root, { recursive: true, withFileTypes: true });
+  return entries
+    .filter((entry) => entry.isFile() && entry.name.endsWith(".json"))
+    .map((entry) => resolve(entry.parentPath, entry.name))
+    .sort();
+}
+
+export function portableRelative(root, path) {
+  return relative(root, path).split(sep).join("/");
+}
+
+export function sha256(source) {
+  return createHash("sha256").update(source).digest("hex");
+}
+
+function collectReferences(value, output = []) {
+  if (Array.isArray(value)) {
+    for (const item of value) collectReferences(item, output);
+    return output;
+  }
+  if (value === null || typeof value !== "object") return output;
+  for (const [key, child] of Object.entries(value)) {
+    if (key === "$ref" && typeof child === "string") output.push(child);
+    else collectReferences(child, output);
+  }
+  return output;
+}
+
+function resolveJsonPointer(value, fragment) {
+  if (fragment === "") return value;
+  if (!fragment.startsWith("/")) return undefined;
+  return fragment
+    .slice(1)
+    .split("/")
+    .map((part) => part.replaceAll("~1", "/").replaceAll("~0", "~"))
+    .reduce((current, part) => {
+      if (current === null || typeof current !== "object") return undefined;
+      return Object.hasOwn(current, part) ? current[part] : undefined;
+    }, value);
+}
+
+export async function loadSchemaCatalog(schemaDirectory) {
+  const files = await listJsonFiles(schemaDirectory);
+  const records = await Promise.all(files.map(async (path) => ({ path, ...(await readJson(path)) })));
+  const ids = new Map();
+
+  for (const record of records) {
+    const schema = record.value;
+    if (schema.$schema !== JSON_SCHEMA_DIALECT) {
+      throw contractError("unsupported_schema_dialect", portableRelative(schemaDirectory, record.path));
+    }
+    if (typeof schema.$id !== "string" || !schema.$id.startsWith(PRP_SCHEMA_ID_PREFIX)) {
+      throw contractError("invalid_schema_id", portableRelative(schemaDirectory, record.path));
+    }
+    if (ids.has(schema.$id)) throw contractError("duplicate_schema_id", schema.$id);
+    if (typeof schema.title !== "string" || schema.title.length === 0) {
+      throw contractError("missing_schema_title", schema.$id);
+    }
+    ids.set(schema.$id, record);
+  }
+
+  for (const record of records) {
+    for (const reference of collectReferences(record.value)) {
+      const [targetId, fragment = ""] = reference.split("#", 2);
+      const target = targetId === "" ? record : ids.get(targetId);
+      if (target === undefined) {
+        throw contractError("unresolved_schema_reference", `${record.value.$id} -> ${reference}`);
+      }
+      if (resolveJsonPointer(target.value, fragment) === undefined) {
+        throw contractError("unresolved_schema_fragment", `${record.value.$id} -> ${reference}`);
+      }
+    }
+  }
+
+  return records;
+}
+
+export function compileProtocolValidators(schemaRecords) {
+  const ajv = new Ajv2020({
+    allErrors: true,
+    strict: true,
+    strictRequired: false,
+    formats: {
+      "date-time": /^\d{4}-\d{2}-\d{2}T\d{2}:\d{2}:\d{2}(?:\.\d{3})?Z$/,
+    },
+  });
+  for (const record of schemaRecords) ajv.addSchema(record.value);
+
+  const get = (name) => {
+    const id = `${PRP_SCHEMA_ID_PREFIX}${name}.schema.json`;
+    const validator = ajv.getSchema(id);
+    if (validator === undefined) throw contractError("missing_schema_validator", id);
+    return validator;
+  };
+  return {
+    conformanceFixture: get("conformance-fixture"),
+    conformanceOutput: get("conformance-output"),
+    fixture: get("fixture"),
+    questionAdapterFixture: get("question-adapter-fixture"),
+  };
+}
+
+export function assertSchemaInstance(validator, value, location, expectedValid = true) {
+  const valid = validator(value);
+  if (valid !== expectedValid) {
+    const detail = (validator.errors ?? [])
+      .slice(0, 8)
+      .map((error) => `${error.instancePath || "/"} ${error.message}`)
+      .join("; ");
+    const expectation = expectedValid ? "accepted" : "rejected";
+    throw contractError("schema_validation_failed", `${location} must be ${expectation}: ${detail || "no AJV error"}`);
+  }
+  return value;
+}
+
+function requireSchema(value, expected, location) {
+  if (value?.schema !== expected) {
+    throw contractError("unsupported_required_schema", `${location} requires ${String(value?.schema)}`);
+  }
+}
+
+function requireVersion(value, expected, name) {
+  if (value !== expected) {
+    throw contractError("unsupported_required_version", `${name}=${String(value)}; supported=${expected}`);
+  }
+}
+
+export function assertReplayFixtureCompatibility(fixture) {
+  requireSchema(fixture, "paperclip.prp.fixture.v1", "fixture");
+  requireVersion(fixture.fixtureVersion, SUPPORTED_FIXTURE_VERSION, "fixtureVersion");
+  requireVersion(fixture.protocolVersion, SUPPORTED_PROTOCOL_VERSION, "protocolVersion");
+  requireSchema(fixture.identity, "paperclip.prp.identity.v1", "identity");
+  requireSchema(fixture.capabilities, "paperclip.prp.capabilities.v1", "capabilities");
+
+  if (!Array.isArray(fixture.commands)) throw contractError("invalid_fixture", "commands must be an array");
+  for (const [index, command] of fixture.commands.entries()) {
+    requireSchema(command, "paperclip.prp.command.v1", `commands[${index}]`);
+  }
+
+  if (!Array.isArray(fixture.events) || fixture.events.length === 0) {
+    throw contractError("invalid_fixture", "events must be a non-empty array");
+  }
+  for (const [index, event] of fixture.events.entries()) {
+    requireSchema(event, "paperclip.prp.event.v1", `events[${index}]`);
+    requireVersion(event.schemaVersion, SUPPORTED_EVENT_SCHEMA_VERSION, `events[${index}].schemaVersion`);
+  }
+
+  requireSchema(fixture.result, "paperclip.run_result.v1", "result");
+  return fixture;
+}
+
+export function assertCodexQuestionFixture(fixture) {
+  requireSchema(fixture, "paperclip.question_adapter_fixture.v1", "question fixture");
+  if (fixture.adapter !== "codex") throw contractError("unsupported_provider", String(fixture.adapter));
+  requireSchema(fixture.canonicalQuestionSet, "paperclip.question_set.v1", "canonicalQuestionSet");
+  requireSchema(fixture.canonicalResponse, "paperclip.question_response.v1", "canonicalResponse");
+  if (fixture.nativeRequest?.method !== "item/tool/requestUserInput") {
+    throw contractError("invalid_codex_question_fixture", "native request method");
+  }
+
+  const questions = fixture.canonicalQuestionSet.questions;
+  if (!Array.isArray(questions) || questions.length === 0) {
+    throw contractError("invalid_codex_question_fixture", "questions must be non-empty");
+  }
+  const questionIds = new Set();
+  const optionIdsByQuestion = new Map();
+  for (const question of questions) {
+    if (typeof question.id !== "string" || question.id.length === 0 || questionIds.has(question.id)) {
+      throw contractError("invalid_codex_question_fixture", "question IDs must be unique");
+    }
+    questionIds.add(question.id);
+    const optionIds = new Set();
+    for (const option of question.options ?? []) {
+      if (typeof option.id !== "string" || option.id.length === 0 || optionIds.has(option.id)) {
+        throw contractError("invalid_codex_question_fixture", `option IDs for ${question.id} must be unique`);
+      }
+      optionIds.add(option.id);
+    }
+    optionIdsByQuestion.set(question.id, optionIds);
+  }
+  for (const [answerId, answer] of Object.entries(fixture.canonicalResponse.answers ?? {})) {
+    if (!questionIds.has(answerId)) {
+      throw contractError("invalid_codex_question_fixture", `answer has unknown question ID ${answerId}`);
+    }
+    for (const optionId of answer.selectedOptionIds ?? []) {
+      if (!optionIdsByQuestion.get(answerId)?.has(optionId)) {
+        throw contractError("invalid_codex_question_fixture", `answer has unknown option ID ${optionId}`);
+      }
+    }
+  }
+  return fixture;
+}
+
+export function assertConformanceFixturePair(fixture, output) {
+  if (fixture?.schemaVersion !== "paperclip.runner.conformance.fixture.v1") {
+    throw contractError("unsupported_required_schema", `conformance fixture requires ${String(fixture?.schemaVersion)}`);
+  }
+  if (output?.schemaVersion !== "paperclip.runner.conformance.output.v1") {
+    throw contractError("unsupported_required_schema", `conformance output requires ${String(output?.schemaVersion)}`);
+  }
+  if (fixture.run?.runId !== output.runIdentity?.runId || fixture.run?.sessionId !== output.runIdentity?.sessionId) {
+    throw contractError("conformance_identity_mismatch", "run or session identity differs");
+  }
+  for (const [index, event] of (fixture.events ?? []).entries()) {
+    if (event.runId !== fixture.run.runId || event.sequence !== index + 1) {
+      throw contractError("invalid_conformance_event", `events[${index}] does not match the run sequence`);
+    }
+  }
+  if (
+    fixture.result?.status !== output.result?.status
+    || fixture.result?.summary !== output.result?.summary
+    || fixture.result?.runId !== fixture.run.runId
+  ) {
+    throw contractError("conformance_result_mismatch", "expected output does not match the fixture result");
+  }
+  return { fixture, output };
+}
diff --git a/packages/paperclip-runner/test/protocol-contract.test.mjs b/packages/paperclip-runner/test/protocol-contract.test.mjs
new file mode 100644
index 0000000000..523b79f5ac
--- /dev/null
+++ b/packages/paperclip-runner/test/protocol-contract.test.mjs
@@ -0,0 +1,110 @@
+import assert from "node:assert/strict";
+import { readFile } from "node:fs/promises";
+import { dirname, resolve } from "node:path";
+import test from "node:test";
+import { fileURLToPath } from "node:url";
+
+import { buildProtocolManifest } from "../scripts/generate-protocol-manifest.mjs";
+import {
+  assertCodexQuestionFixture,
+  assertConformanceFixturePair,
+  assertReplayFixtureCompatibility,
+  assertSchemaInstance,
+  compileProtocolValidators,
+  loadSchemaCatalog,
+  readJson,
+} from "../scripts/protocol-contract.mjs";
+
+const packageRoot = resolve(dirname(fileURLToPath(import.meta.url)), "..");
+const protocolRoot = resolve(packageRoot, "protocol");
+
+async function fixture(relativePath) {
+  return (await readJson(resolve(protocolRoot, "fixtures", relativePath))).value;
+}
+
+test("all schema IDs are unique and all external references resolve", async () => {
+  const schemas = await loadSchemaCatalog(resolve(protocolRoot, "schemas"));
+  assert.equal(schemas.length, 20);
+  assert.doesNotThrow(() => compileProtocolValidators(schemas));
+});
+
+test("the generated manifest matches all checked-in schemas and fixtures", async () => {
+  const expected = `${JSON.stringify(await buildProtocolManifest(), null, 2)}\n`;
+  const actual = await readFile(resolve(protocolRoot, "manifest.json"), "utf8");
+  assert.equal(actual, expected);
+});
+
+test("canonical replay fixtures use supported required versions", async () => {
+  for (const name of [
+    "duplicate-event.json",
+    "failed-run.json",
+    "happy-path.json",
+    "interrupted-run.json",
+    "source-gap.json",
+  ]) {
+    assert.equal(assertReplayFixtureCompatibility(await fixture(`replay/${name}`)).protocolVersion, 1);
+  }
+});
+
+test("unknown additive fields remain compatible with PRP v1", async () => {
+  const value = await fixture("replay/unknown-optional-fields.json");
+  assert.equal(value.futureFixtureHint.producerVersion, "1.1-preview");
+  assert.doesNotThrow(() => assertReplayFixtureCompatibility(value));
+});
+
+test("unknown required versions and schemas fail closed", async () => {
+  const unsupported = await fixture("replay/unsupported-required-version.json");
+  assert.throws(
+    () => assertReplayFixtureCompatibility(unsupported),
+    /unsupported_required_version: protocolVersion=2; supported=1/,
+  );
+
+  const eventVersion = structuredClone(await fixture("replay/happy-path.json"));
+  eventVersion.events[0].schemaVersion = 2;
+  assert.throws(() => assertReplayFixtureCompatibility(eventVersion), /unsupported_required_version/);
+
+  const commandSchema = structuredClone(await fixture("replay/happy-path.json"));
+  commandSchema.commands[0].schema = "paperclip.prp.command.v2";
+  assert.throws(() => assertReplayFixtureCompatibility(commandSchema), /unsupported_required_schema/);
+});
+
+test("accepted fixtures satisfy the complete JSON Schemas", async () => {
+  const schemas = await loadSchemaCatalog(resolve(protocolRoot, "schemas"));
+  const validators = compileProtocolValidators(schemas);
+  const happyPath = await fixture("replay/happy-path.json");
+  assert.doesNotThrow(() => assertSchemaInstance(validators.fixture, happyPath, "happy-path"));
+
+  const missingRequiredField = structuredClone(happyPath);
+  delete missingRequiredField.commands[0].commandId;
+  assert.throws(
+    () => assertSchemaInstance(validators.fixture, missingRequiredField, "missing-command-id"),
+    /schema_validation_failed: missing-command-id must be accepted: \/commands\/0 must have required property 'commandId'/,
+  );
+
+  const unsupported = await fixture("replay/unsupported-required-version.json");
+  assert.doesNotThrow(() => assertSchemaInstance(validators.fixture, unsupported, "required-v2", false));
+});
+
+test("the Codex question fixture uses stable provider-neutral IDs", async () => {
+  const value = await fixture("questions/codex.json");
+  assert.doesNotThrow(() => assertCodexQuestionFixture(value));
+  assert.deepEqual(Object.keys(value.canonicalResponse.answers), ["environment"]);
+});
+
+test("the cross-language conformance input and output have one stable identity", async () => {
+  const input = await fixture("conformance-minimal-run.json");
+  const output = await fixture("conformance-expected-output.json");
+  const schemas = await loadSchemaCatalog(resolve(protocolRoot, "schemas"));
+  const validators = compileProtocolValidators(schemas);
+  assert.doesNotThrow(() => assertSchemaInstance(validators.conformanceFixture, input, "conformance-input"));
+  assert.doesNotThrow(() => assertSchemaInstance(validators.conformanceOutput, output, "conformance-output"));
+  assert.doesNotThrow(() => assertConformanceFixturePair(input, output));
+  assert.equal(input.result.summary, output.result.summary);
+
+  const missingSessionId = structuredClone(output);
+  delete missingSessionId.runIdentity.sessionId;
+  assert.throws(
+    () => assertSchemaInstance(validators.conformanceOutput, missingSessionId, "missing-session-id"),
+    /schema_validation_failed: missing-session-id must be accepted: \/runIdentity must have required property 'sessionId'/,
+  );
+});