## Thinking Path
> - Paperclip is the open source app people use to manage AI agents for
work.
> - The runner package already provides the production protocol and
execution spine.
> - Contributors still need stable SDK surfaces, deterministic test
tools, and local inspection tools.
> - Those surfaces share generated contracts and must change as one
package boundary.
> - This pull request adds the package-local SDK, labs, examples, and
drift checks.
> - The benefit is a reviewable developer platform that does not change
application execution selection.
## Linked Issues or Issue Description
**Subsystem affected**
`packages/paperclip-runner` — runner SDK, conformance tools, and
developer tooling.
**Problem or motivation**
The production runner spine is present, but package consumers cannot
build deterministic integrations, inspect sessions, or verify
provider-neutral behavior through supported surfaces.
**Proposed solution**
Add browser, React, standalone, live-session, scenario, conformance, and
evaluation surfaces. Add generated contract inventories and
package-local verification scripts. Keep production application routing
unchanged.
**Alternatives considered**
We considered splitting each generated catalog, SDK surface, and demo
into separate pull requests. Those changes share exports, fixtures, and
drift gates. Splitting them would create intermediate package states
that do not build.
**Roadmap alignment**
No overlapping item appears in `ROADMAP.md`. This work extends the
runner package that is already on `master`.
## What Changed
- Add browser, React, standalone, live-session, and issue-thread SDK
surfaces.
- Add deterministic mock control-plane, scenario, conformance, replay,
and evaluation tools.
- Add bounded Codex, OpenCode, and ACPX development transports and
fixtures.
- Keep deferred managed-provider execution fail-closed. Persisted
compatibility data remains readable.
- Add generated capability inventories with their source files and drift
checks.
- Add examples, package documentation, browser checks, and
clean-consumer checks.
- Preserve the reviewed protocol bounds, replay compatibility aliases,
process environment isolation, and semantic redaction limits.
- Update the ACPX package patch that the existing workspace patch
registry already tracks.
- Do not change `pnpm-lock.yaml`, repository workflows, server runtime
selection, or the application UI.
## Verification
GitHub Actions is the verification authority for this pull request. The
repository CI, package TypeScript and Rust checks, package tests,
generated-output drift checks, browser checks, security scans, and
Greptile review must pass on the exact head.
Local test suites were not run because this series uses parallel GitHub
Actions for verification.
## Risks
This is a large greenfield package change. The main risks are public
export drift, generated-output drift, and optional React consumer
compatibility. Package boundary checks, clean-consumer checks, and
browser tests cover those risks. Production adapter selection and server
execution are outside this pull request.
## Stack
1. **This PR:** runner SDK and developer tooling.
2. [Codex production server
integration](https://github.com/paperclipai/paperclip/pull/12616).
3. [Provider-neutral task-thread
UI](https://github.com/paperclipai/paperclip/pull/12617).
## Model Used
OpenAI Codex, GPT-5, high-reasoning mode, with tool use and code
execution.
## Checklist
- [x] I have included a thinking path that traces from project context
to this change
- [x] I have specified the model used (with version and capability
details)
- [x] I have checked ROADMAP.md and confirmed this PR does not duplicate
planned core work
- [x] I have searched GitHub for duplicate or related PRs and linked
them above
- [x] I have described the issue in-PR following the feature request
template
- [x] I have not referenced internal/instance-local Paperclip issues or
links
- [x] My branch name describes the change and contains no internal
Paperclip ticket id
- [ ] I have run tests locally and they pass
- [x] I have added or updated tests where applicable
- [x] I have updated relevant documentation to reflect my changes
- [x] I have considered and documented risks above
- [ ] All Paperclip CI gates are green
- [ ] Greptile is 5/5 with no open P2s, recommendations, or follow-ups
- [x] I will address all Greptile and reviewer comments before
requesting merge
## Thinking Path
> - Paperclip is the open source app people use to manage AI agents for
work.
> - Paperclip Runner needs a small local process model before it can
connect to a production provider or server.
> - The TypeScript PRP contracts now define the expected replay
behavior.
> - A second language implementation must produce the same result from
the same fixtures.
> - Local child processes also need bounded input, bounded output, and
complete descendant cleanup.
> - This pull request adds a package-local Rust runner, a scripted fake
harness, and deterministic parity checks.
> - The benefit is a testable process boundary with no production
Paperclip behavior change.
## Linked Issues or Issue Description
**Subsystem affected**
Cross-cutting. This pull request adds private test infrastructure to
`packages/paperclip-runner`.
**Problem or motivation**
The PRP contracts have no second implementation on `master`. There is
also no small harness that can prove process cleanup, command
idempotency, terminal reconciliation, or bounded JSONL handling without
a production provider.
**Proposed solution**
Add a minimal Rust workspace. Add a local runner process, a scripted
fake harness, a bounded process supervisor, and Rust conformance and
replay checks. Keep all binaries package-local. Do not connect them to
the Paperclip server.
**Alternatives considered**
The combined runner branch includes provider transports, durable
networking, SDKs, labs, and server behavior. That change is too large
for this review unit. A TypeScript-only harness would not test
cross-language contract parity.
**Roadmap alignment**
This work supports the governed tools and self-healing run direction in
`ROADMAP.md`. It does not add a user-facing runtime, adapter, endpoint,
or rollout flag.
**Additional context**
Refs #12091 and #11962. Pull request #12091 was merged before this
branch opened. This branch is based on the current `master`. Its delta
is 25 files.
## What Changed
- Added a minimal locked Rust workspace with only `serde` and
`serde_json` dependencies.
- Added a package-local `paperclip-runnerd` local mode and a scripted
fake harness.
- Added bounded controller input, harness input, subprocess output
queues, line sizes, log retention, script sizes, script steps, and
command history.
- Added contiguous controller and harness sequence checks and
equivalent-command replay handling.
- Added process-group supervision that cleans up child processes and
remaining descendants after forced or natural harness exit.
- Added runner-owned terminal reconciliation for success, failure,
interruption, cancellation, controller closure, and protocol failure.
- Added Rust conformance output and deterministic replay summaries for
the shared PRP fixtures.
- Added fake scripts for success, failure, interruption, interaction,
duplicate terminal output, process cleanup, and oversized output.
- Added package scripts and documentation for the Rust and
cross-language checks.
- Kept provider transport, server integration, semantic tools, and
production runtime selection out of this pull request.
## Verification
- `pnpm --filter @paperclipai/paperclip-runner check:all` passes.
- TypeScript contract tests pass: 8 Node tests and 44 Vitest tests.
- Rust tests pass: 20 unit tests, 2 local-runner tests, and 3
process-supervisor tests.
- The Rust conformance and replay parity checks pass against the shared
fixtures.
- The natural-exit and forced-exit tests confirm that the harness and
its worker process are stopped.
- The oversized-frame test confirms that a harness frame above the
configured limit is rejected.
- `pnpm -r typecheck` passes after the final rebase to `master`.
- `pnpm build` passes after the final rebase to `master`.
- `pnpm check:token-gates` passes.
- `git diff --check` passes.
- The delta against `master` is 25 files. The package lockfile is
unchanged.
- `pnpm test:run` completed locally with 4,686 passing tests, 19 skipped
tests, and 30 failures in 8 unchanged server test files. The failures
are local macOS path-alias, listener, port-range, and workspace-runtime
baseline failures. No changed-file test failed, and every applicable
Linux CI shard passes.
- Storybook visual regression skipped intentionally because this pull
request changes no UI or story files.
## Risks
Low production risk. No server code invokes the new binaries. The
package remains private. The main risks are process leaks, unbounded
local input, and cross-language drift. Bounded queues and sizes,
process-group cleanup tests, fixture manifests, and parity checks cover
these risks.
I checked `ROADMAP.md`. This change is private test infrastructure for
planned control-plane work. It does not duplicate a shipped or public
product surface.
## Model Used
OpenAI Codex with GPT-5 was used. The exact serving model ID and context
size were not exposed. The model used high reasoning, repository tools,
GitHub tools, and local code execution.
## Checklist
- [x] I have included a thinking path that traces from project context
to this change
- [x] I have specified the model used (with version and capability
details)
- [x] I have checked ROADMAP.md and confirmed this PR does not duplicate
planned core work
- [x] I have searched GitHub for duplicate or related PRs and linked
them above
- [x] I have either (a) linked existing issues with `Fixes: #` / `Closes
#` / `Refs #` OR (b) described the issue in-PR following the relevant
issue template
- [x] I have not referenced internal/instance-local Paperclip issues or
links (only public GitHub `#NNN` / `github.com/paperclipai/paperclip`
URLs)
- [x] My branch name describes the change (e.g. `docs/...`, `fix/...`)
and contains no internal Paperclip ticket id or instance-derived details
- [ ] I have run tests locally and they pass
- [x] I have added or updated tests where applicable
- [x] I have updated relevant documentation to reflect my changes
- [x] I have considered and documented any risks above
- [x] All Paperclip CI gates are green
- [x] Greptile is 5/5 with no open P2s, recommendations, or follow-ups
- [x] I will address all Greptile and reviewer comments before
requesting merge
---------
Co-authored-by: Paperclip <noreply@paperclip.ing>
Co-authored-by: Paperclip <noreply@paperclip.ing>
Dotta