## Thinking Path
> - Paperclip is the open source app people use to manage AI agents for
work.
> - Paperclip Runner gives native runs a durable and governed execution
path.
> - The current native path runs on the control-plane host.
> - Remote environments need an authenticated execution-target contract.
> - The contract must not change direct adapters or enable new runtimes
by default.
> - This pull request adds the remote execution substrate and Daytona
ingress.
> - The benefit is a bounded base for later remote runner transport
work.
## Linked Issues or Issue Description
Refs #12616.
Refs #12352.
**Subsystem affected**
Cross-cutting. This change touches runner transport, server
orchestration, plugin contracts, and shared settings.
**Problem or motivation**
Native execution cannot resolve an authenticated runner ingress through
a remote environment. The server also lacks one provider-neutral
contract for remote execution targets.
**Proposed solution**
Add a default-off runner preview ingress capability. Add
transport-neutral runner connectivity. Add remote execution target and
lifecycle handling. Add a Daytona ingress implementation with redacted
credentials.
**Alternatives considered**
A provider-specific server path would duplicate orchestration and
authorization. A public endpoint without an environment contract would
weaken the trust boundary.
**Roadmap alignment**
This work supports the Cloud and Sandbox agents milestone. It also
supports self-healing runs and governed tool access.
## What Changed
- Added execution-target traits for local, SSH, and sandbox
environments.
- Added plugin RPC contracts for runner ingress endpoints.
- Added authenticated Daytona preview ingress.
- Added transport-neutral PRP outbound connections.
- Added remote runner artifact verification and fail-closed provider
selection.
- Added bounded native session resume, cancellation, and lifecycle
recovery.
- Preserved Codex-only selection for fresh experimental runner starts.
- Preserved all direct adapter execution and finalization paths.
- Removed stale Pi provider-pack requirements that security review
rejected.
- Kept the rollout controls off by default.
- Did not change pnpm-lock.yaml, Cargo, database migrations, or GitHub
workflows.
## Verification
- GitHub Actions will run the repository test, typecheck, build,
security, and policy gates.
- Focused tests cover ingress validation, redaction, execution targets,
remote lifecycle, cancellation, resume, and legacy adapter selection.
- Local tests were not run. The requested verification policy uses
GitHub Actions for this series.
- `git diff --check origin/master...HEAD` passes.
- The diff contains 52 files.
## Risks
- Remote execution crosses a trust boundary.
- The implementation validates target capabilities, artifact digests,
provider-pack pins, and connection metadata.
- The feature remains default-off.
- Fresh native selection remains Codex-only.
- Existing direct adapters remain on the legacy path.
- This PR does not yet make remote Codex runnable. The next PR adds the
Rust WSS and TLS transport.
## Model Used
OpenAI Codex with GPT-5.6. The work used high-reasoning agent mode,
repository tools, GitHub tools, and parallel code-audit agents.
## 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 or 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.
> - The runner package is useful only when the application can start,
observe, and recover a native Codex run safely.
> - Existing direct adapters must keep their current execution and
finalization paths.
> - The application boundary therefore needs additive persistence,
authorization, coordination, and recovery behind an explicit
experimental adapter.
> - This pull request adds that Codex-only boundary without activating
generalized providers, remote environments, or the later task/SDK
surfaces.
## Linked Issues or Issue Description
**Subsystem affected**
Shared contracts, database persistence, adapter utilities, server
native-runtime services, and the experimental Paperclip Runner adapter.
**Problem or motivation**
The already-landed runner package has a qualified Codex path, but the
application needs durable native-run state, guarded runtime selection,
authenticated coordination, tool security, finalization, and recovery
before the experimental adapter can be exercised safely.
**Proposed solution**
Add a Codex-only `paperclip_runner` application path behind the existing
default-off native-runner setting. Bind native state and coordination to
company/run identity, preserve persisted-run recovery, and leave every
direct adapter on its existing legacy execution path.
**Alternatives considered**
The earlier stack boundary introduced a generalized executor and
remote-environment lifecycle here. That made this PR depend on
implementations in higher PRs and changed reusable sandbox behavior
globally. Those pieces are now deferred together to #12592.
**Roadmap alignment**
ROADMAP.md does not list a conflicting native-runner integration
project. This change adds the application boundary for the existing
Runner architecture.
## What Changed
- Added native run/result/finalization/provider-trace persistence,
shared validators, and idempotent migration/replay coverage.
- Added guarded Codex-only runtime selection, authenticated PRP
coordination, recovery, finalization, and interaction services.
- Added run/company-bound tool-gateway authorization, credential
redaction, SSRF protections, and replay-safe behavior.
- Added the explicit `paperclip_runner` adapter behind the default-off
rollout setting.
- Preserved legacy answered-question wake projection and direct-adapter
execution/finalization paths.
- Hardened cancellation so only owned in-memory child processes are
signaled; persisted recycled PIDs/process groups are never trusted.
- Retained the narrow Claude ACPX isolated-context security follow-up
discovered after #12590.
- Deferred the generalized executor, provider ingress, remote lifecycle,
SDK/lab/eval work, release-process changes, and lockfile.
## Verification
- Changed-file delta against `master`: 133 files.
- GitHub Actions is the authoritative verification environment for this
PR.
- Full CI, security, and Greptile review will run on this lowest
unmerged stack PR.
- Local tests/build/typecheck were not run because this checkout is
resource constrained.
- Static diff/reference checks pass, and `pnpm-lock.yaml` is unchanged.
## Risks
- This touches central heartbeat and agent-route code, so legacy
compatibility is the primary risk.
- Runtime selection remains Codex-only and explicit; direct Codex,
Claude, OpenCode, process, HTTP, and plugin adapters remain on their
existing paths.
- Fresh native starts fail closed while the rollout flag is off;
persisted native records remain readable and recoverable.
- Cancellation, company/run binding, tool calls, status decisions, and
completion writes are guarded or replay-safe.
> For core feature work, check [ROADMAP.md](ROADMAP.md) first and
discuss it in #dev before opening the PR. Feature PRs that overlap with
planned core work may need to be redirected.
## Model Used
OpenAI Codex, GPT-5.6, with repository tools, code execution, and
parallel agent review.
## 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 linked existing issues or described the issue in-PR
following the relevant issue template
- [x] I have not referenced internal or 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 — GitHub Actions is
authoritative for this resource-constrained checkout
- [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 and security gates are green
- [ ] Greptile is 5/5 with no open actionable findings
- [x] I will address all Greptile and reviewer comments before merge
## Stack
- Position: 3 of 5 overall; lowest of 3 currently unmerged
- Base: `master`
- Previous:
[#12590](https://github.com/paperclipai/paperclip/pull/12590), qualified
Claude ACPX runtime — merged
- Next: [#12592](https://github.com/paperclipai/paperclip/pull/12592),
generalized Codex executor, task experience, and developer SDKs
---------
Co-authored-by: Dev Agent <dev@paperclip.ing>
## Thinking Path
> - Paperclip is the open source app people use to manage AI agents for
work.
> - The adapter layer carries sandbox requests to host processes.
> - The HTTP/2 bridge used one process-wide byte ledger for all routes.
> - One busy route could exhaust that shared budget and move another
route to file transport.
> - This pull request gives each host retention site a fixed byte bound
and limits concurrent HTTP/2 streams.
> - The benefit is local protection: one route cannot consume the byte
budget of another route.
## Linked Issues or Issue Description
**What happened?**
The HTTP/2 bridge used one aggregate byte ledger for retained bytes
across all routes. A busy route could exhaust the shared budget and
force an unrelated route to use file transport.
**Expected behavior**
Each route should protect its own retained bytes. A reset on one HTTP/2
stream should cancel only that stream's host forward.
**Steps to reproduce**
1. Start the HTTP/2 bridge with multiple sandbox routes.
2. Send enough retained data through one route to reach the aggregate
byte limit.
3. Send a request through a sibling route.
4. Observe that the sibling route can fall back to file transport
because the first route used the shared ledger.
**Paperclip version or commit**
`47639e227e78e3c5e0dd1a3c0e2d792fe86895a3`
**Deployment mode**
Built from source with the adapter-utils and server test suites.
## What Changed
- Bound each host retention site with a fixed local byte limit.
- Limited concurrent live HTTP/2 streams with one built-in stream limit.
- Bound each host forward and response-body read to its own HTTP/2
stream lifetime.
- Removed the process-wide byte ledger, its environment override, its
metrics, and its file-transport fallbacks.
- Added tests for the stream limit, host body budget, and sibling-stream
cancellation.
## Verification
- Run `pnpm vitest run --project adapter-utils`.
- Confirm that 996 adapter-utils tests pass.
- Confirm that `test_live_forward_work_never_passes_the_stream_limit`
passes.
- Confirm that `test_the_host_body_budget_matches_the_stream_limit`
passes.
- Confirm that the sibling-stream cancellation test passes.
- Run `pnpm tsc --noEmit`.
- Confirm that all pull request checks pass.
## Risks
The bridge no longer uses a process-wide byte ledger. A local bound or
stream limit that is too low can reject or delay valid work. The tests
cover the new limits and stream cancellation behavior.
## Model Used
OpenAI GPT-5 Codex. Runtime model ID: GPT-5. The model used code
execution and repository tools. The runtime does not expose the context
window size.
## 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
- [x] 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>
## Thinking Path
> - Paperclip is the open source app people use to manage AI agents for
work
> - Sandbox providers carry agent work through controlled execution
channels
> - The Daytona callback bridge uses a bespoke line-framed protocol over
its duplex channel
> - The bespoke protocol adds framing work and does not use the Node
transport that already supports multiplexed streams
> - This pull request carries raw bytes across the channel, adds a Node
HTTP/2 bridge, and selects it for Daytona
> - The benefit is one authenticated, multiplexed callback session with
queue_v1 as the bounded fallback
## Linked Issues or Issue Description
**Subsystem affected**
The packages/plugins Daytona provider and the shared duplex execution
path.
**Problem or motivation**
The Daytona callback bridge uses a bespoke line-framed protocol over the
provider duplex channel. This adds protocol work and limits stream
handling.
**Proposed solution**
Carry raw bytes through the cross-layer channel. Add an authenticated
Node HTTP/2 host server and sandbox client gateway. Select http2_v1 for
Daytona and retain queue_v1 as the fallback.
**Alternatives considered**
Keep the current duplex_v1 protocol. This keeps the bespoke framing path
and does not provide one HTTP/2 session for callback streams.
**Roadmap alignment**
ROADMAP.md lists Daytona under cloud and sandbox agents. This change
improves the shipped Daytona provider path.
**Additional context**
The branch adds no dependency. Node 24 provides the http2 module. The
host token check and canonical path parser remain the single dispatch
path.
## What Changed
- Carry raw Uint8Array chunks through the adapter, plugin, worker,
runtime, and Daytona layers.
- Encode bytes as base64 only across the JSON-RPC hop, because JSON has
no binary type.
- Add the bounded host HTTP/2 server and the in-sandbox HTTP/2 client
gateway.
- Authenticate every stream with the per-run bridge token before route
work.
- Parse the path once and reuse the canonical result for route and
forwarding work.
- Select http2_v1 for Daytona and fall back once to queue_v1 when the
client preface is absent.
- Add transport, session, stream, and fallback telemetry.
- Mark HTTP/2 as the preferred transport and queue_v1 as the
soft-deprecated fallback.
## Verification
- `npx vitest run packages/adapter-utils/src` — 990 passed and 4
skipped.
- `npx vitest run
server/src/__tests__/plugin-worker-manager-duplex.test.ts` — 32 passed.
- `npx vitest run --config
packages/plugins/sandbox-providers/daytona/vitest.config.ts` — 220
passed and 6 skipped.
- `npx tsc --noEmit` in `packages/adapter-utils`, `packages/shared`,
`packages/plugins/sdk`, and `server` — clean.
- No `package.json` or `pnpm-lock.yaml` file changed.
- The live Daytona test skips when `DAYTONA_API_KEY` is absent.
- The root `npx tsc --noEmit` command has a pre-existing missing
`packages/adapters/droid-local` reference on this branch and on
`master`.
## Risks
- The transport change affects several duplex layers and could expose
byte-boundary errors.
- A missing HTTP/2 client preface falls back once to queue_v1 and
records `preface_missing`.
- The host token check and canonical path parser must remain on the
shared dispatch path.
- The live Daytona test needs `DAYTONA_API_KEY` and does not run in this
agent sandbox.
## Model Used
OpenAI GPT-5, tool-enabled coding agent with repository inspection,
GitHub CLI, and shell 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
- [x] 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>
## Thinking Path
> - Paperclip is the open source app people use to manage AI agents for
work
> - The adapter utilities package defines shared types for agent
execution targets
> - The type name EffectiveSandboxCapabilities describes only one
transport
> - All execution target drivers return the same resolved capability
snapshot
> - This pull request gives the snapshot a general name and keeps the
old type as a deprecated alias
> - The benefit is clearer public vocabulary with source compatibility
for current consumers
## Linked Issues or Issue Description
**What existing behavior does this improve?**
The exported capability snapshot type uses the name
`EffectiveSandboxCapabilities`, although local, SSH, sandbox, and plugin
drivers return it.
**Subsystem affected**
The change affects `packages/adapter-utils` and its server consumers.
**Current behavior**
The public type name points to the sandbox transport. The private parser
also uses the sandbox-only name.
**Proposed behavior**
Use `EffectiveExecutionCapabilities` for the public type and
`parseEffectiveExecutionCapabilities` for the private parser. Keep a
deprecated alias for the old public type.
**Reason and benefit**
The new name matches the established execution-target vocabulary. The
alias keeps existing type imports working during the migration.
**Breaking changes**
None. The runtime field, capability flags, parsed shape, and package
versions do not change.
**Additional context**
GitHub search found no duplicate or related open issue or pull request.
## What Changed
- Rename the exported interface to `EffectiveExecutionCapabilities`.
- Keep `EffectiveSandboxCapabilities` as a deprecated type alias.
- Rename the private parser and update its call site and references.
- Add a type-level test for the deprecated alias.
## Verification
- `npx tsc --noEmit -p packages/adapter-utils`
- `npx vitest run
packages/adapter-utils/src/execution-target-sandbox.test.ts`
- `npx vitest run
server/src/__tests__/environment-execution-target-capabilities.test.ts
server/src/__tests__/environment-execution-target-duplex.test.ts`
- The local checks passed with 133 adapter-utils tests and 31 server
tests.
- Reviewers can confirm that the runtime field and capability flags stay
unchanged.
## Risks
Low risk. The alias protects existing type imports. The change does not
alter runtime behavior or serialized data.
## Model Used
OpenAI Codex, GPT-5, tool use and code execution. The runtime does not
expose the context window size.
## 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
- [x] 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>
## Thinking Path
> - Paperclip is the open source app people use to manage AI agents for
work
> - Environment runtime drivers provide workspace, lease, and custom
image behavior
> - Runtime code used driver identity checks and several
capability-specific members
> - These checks spread capability rules across the runtime and made new
drivers harder to verify
> - This pull request adds one general capability classifier and one
static driver support table
> - The benefit is one fail-closed capability model that keeps current
behavior and supports future drivers
## Linked Issues or Issue Description
**What existing behavior does this improve?**
Environment runtime capability checks for workspace realization, custom
images, lease capabilities, and duplex authorization.
**Subsystem affected**
Cross-cutting (multiple of the above)
**Current behavior**
The runtime selects several capability paths from driver identity and
separate capability members. Custom image gates also trust provider
declarations without checking every matching live worker method.
**Proposed behavior**
The runtime uses one general capability classifier and one static
support table. Custom image gates require both the provider declaration
and every matching live worker method. The public capability names
remain unchanged.
**Reason and benefit**
The change keeps capability rules in one place. It removes identity
conditions from runtime consumers and makes unsupported drivers fail
closed.
**Breaking changes**
None. The public names sandboxCapabilities, sandboxProviders, and
EffectiveSandboxCapabilities remain available.
## What Changed
- Add classifyEnvironmentCapabilities and static support definitions for
all four driver families.
- Add resolveCapabilities to every environment runtime driver.
- Move driver traits into environment-driver-traits.ts and migrate
runtime consumers.
- Require provider declarations and matching live worker methods for all
custom image gates.
- Migrate duplex authorization to the general resolver and remove the
dead sandbox-only member.
- Delete the unused resolveEffectiveSandboxCapabilities wrapper and
update its test.
## Verification
- pnpm --filter @paperclipai/server typecheck
- pnpm exec vitest run
server/src/__tests__/environment-capability-contract.test.ts
server/src/__tests__/environment-runtime.test.ts — 92 tests pass
- pnpm exec vitest run
server/src/__tests__/environment-driver-traits.test.ts
server/src/__tests__/general-capability-classifier.test.ts — 12 tests
pass
- pnpm exec vitest run
server/src/__tests__/environment-custom-images-service.test.ts
server/src/__tests__/environment-execution-target-capabilities.test.ts
server/src/__tests__/environment-execution-target-duplex.test.ts
server/src/__tests__/environment-execution-target-duplex-kill-switch.test.ts
— 66 tests pass
## Risks
The main risk is a capability gate that denies a valid driver or permits
an invalid driver. The static support matrix, live worker method checks,
and regression tests reduce this risk. No database, public API, or
published type name changes.
## Model Used
OpenAI Codex, GPT-5, with tool use and code execution. The deployment
does not provide a separate context-window value.
## 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 (for example, docs/... or
fix/...) and contains no internal Paperclip ticket id or
instance-derived details
- [x] 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>
## Thinking Path
> - Paperclip runs AI agents through adapters and sandboxed execution
targets.
> - Duplex routes retain bytes across route data, broker messages,
decoder buffers, and readiness replay.
> - Per-route limits bound each route but do not bound the total
retained bytes across many routes.
> - A process-owned ledger must charge each retained buffer before
allocation and release the charge during cleanup.
> - This pull request adds the aggregate ledger, connects it to host and
sandbox duplex paths, and adds route coverage.
> - The benefit is a fail-closed process-wide byte limit that keeps
concurrent duplex work within a safe resource budget.
## Linked Issues or Issue Description
**Subsystem affected**
This change affects packages/adapter-utils and server duplex
orchestration.
**Problem or motivation**
Many routes can each stay below their per-route limits while their
combined retained bytes exceed a safe process budget.
**Proposed solution**
Add a process-owned aggregate byte ledger. Charge route data, broker
bytes, decoder buffers, and readiness replay bytes before allocation.
Release each charge during cleanup. Use a separate sandbox_process
decoder cap for the in-sandbox path.
**Alternatives considered**
Keep only per-route limits. This does not bound the combined process
use. Set a fixed limit at one call site. This misses retained bytes in
other duplex paths.
**Roadmap alignment**
This is a tightly scoped reliability and resource-safety improvement. It
does not duplicate a roadmap feature.
**Additional context**
The aggregate ceiling uses a safe 256 MiB default. An invalid override
falls back to that default and reports the rejected value.
## What Changed
- Add a process-owned aggregate byte ledger for duplex route resource
use.
- Charge and release route data, broker forward and response bytes,
decoder buffers, and readiness replay bytes.
- Bound host-to-worker pending writes and standard input transport
bytes.
- Add a separate decoder cap for the sandbox_process path.
- Make invalid aggregate-ceiling overrides fall back to the safe default
without host startup failure.
- Add adapter-utils and server tests for charging, release, rejection,
cleanup, and many-route aggregate limits.
## Verification
- pnpm --filter @paperclipai/adapter-utils exec tsc --noEmit
- pnpm --filter @paperclipai/server exec tsc --noEmit
- Run the focused adapter-utils duplex ledger and execution-target
tests.
- Run the server aggregate-ledger route test.
- Confirm all required pull request checks pass on this branch.
## Risks
The ledger touches several duplex buffer paths. A missed release could
reduce later capacity until process restart. The tests cover charge,
release, rejection, cleanup, and route aggregation. The change uses a
safe default when configuration input is invalid.
## Model Used
OpenAI GPT-5 Codex. The runtime model ID and context window are not
exposed to this task. The model used tool calls, shell commands, and
code review workflow support.
## 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 issue references)
- [x] My branch name describes the change and contains no internal
Paperclip ticket id or instance-derived details
- [x] 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>
## Thinking Path
> - Paperclip provides a control plane for companies that run AI agents.
> - Sandboxed agents need a safe execution path for persistent command
streams.
> - The existing callback transport does not provide a bounded, generic
duplex route.
> - The host must control capability access, route identity, protocol
limits, and close behavior.
> - This pull request adds an opt-in duplex command-stream foundation
across the sandbox layers.
> - The feature stays inert because no current provider declares the
capability.
## Linked Issues or Issue Description
**Subsystem affected**
Cross-cutting (multiple of the above)
**Problem or motivation**
Sandbox command execution needs a persistent host-to-sandbox stream. The
current callback bridge uses a file transport and does not provide this
generic route.
**Proposed solution**
Add a fail-closed provider capability, generic worker protocol messages,
a host-owned bounded route, cross-layer service mediation, and a
versioned newline-delimited frame codec.
**Alternatives considered**
Keep the file transport and add feature-specific commands. This does not
provide one reusable duplex contract or host-owned route bounds.
**Roadmap alignment**
This work supports the completed Cloud / Sandbox agents roadmap area and
the safe autonomy goal in the product definition.
**Additional context**
The change passed a two-stage security review. The final code review
verdict was approve after fixes for active-stream bounds and
service-layer capability mediation.
## What Changed
- Add the opt-in `duplexCommandStream` provider capability with
fail-closed narrowing.
- Add duplex open, write, stop, and close requests and data and exit
notifications to the plugin worker protocol.
- Add a host-owned route with bounds for chunk size, cumulative bytes,
lifetime, protocol errors, pending requests, and pre-bind buffering.
- Add close acknowledgement handling with worker retirement when the
close remains unconfirmed.
- Wire `openDuplexChannel` through the execution target, runtime
service, and plugin worker.
- Add a versioned frame codec with shared wire-compatibility vectors and
split UTF-8 handling.
## Verification
- `server/src/__tests__/plugin-worker-manager-duplex.test.ts` passes 18
tests.
- `server/src/__tests__/environment-execution-target-duplex.test.ts`
passes 11 tests.
- `packages/adapter-utils/src/duplex-frame-codec.test.ts` passes 38
tests.
- `server/src/__tests__/sandbox-capability-contract.test.ts` passes 15
tests.
- Setup-token pseudo-terminal regression tests pass 47 tests.
- Server TypeScript check passes.
- Continuous integration will run the full required test, typecheck,
build, and policy checks.
## Risks
- Providers that opt into the capability must implement the complete
worker protocol.
- Route limit defaults can close a stream when a workload exceeds the
configured bounds.
- The capability remains disabled for current providers, so current
production behavior does not change.
## Model Used
OpenAI GPT-5 (`gpt-5`), with tool use and code execution. The model
reviewed and prepared this pull request from the supplied implementation
and verification record.
## 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
- [x] 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>
Dotta
Nicky Leach