## Thinking Path > - Paperclip is the open source app people use to manage AI agents for work > - The Rust runner now owns validated, scoped ACPX reducer events and safe session suspension > - Durable PRP transport must receive provider-neutral events rather than sidecar-native envelopes > - Semantic calls and questions must retain the exact run, session, turn, item, and provider-request authority used by the durable command stream > - Terminal, result, assistant, process, and diagnostic events also need one reviewed projection boundary > - Permission requests remain impossible under the pinned Codex policy and must fail closed if they reach projection > - This pull request adds only that package-local projection without selecting ACPX in runnerd ## Linked Issues or Issue Description Refs #12422 ## What Changed - Add a validated durable ACPX event projection context bound to one run, normalized session, turn, and item. - Pass already normalized activity events through without reintroducing provider-native envelopes. - Project authorized tool calls into canonical semantic input receipts with exact correlation and content digests. - Project structured questions into provider-neutral `paperclip.runtime_request.v2` events. - Preserve both the public projected request identity and the original provider request identity so responses resolve the exact sidecar request. - Project dynamic semantic operation results as `semantic_tool.result`; only reserved finish/block operations may propose the run result. - Project semantic completion results into `run.result.proposed`. - Project terminal-flushed assistant messages on the final channel and turn terminal states into existing provider-neutral event families. - Project sanitized process metadata and diagnostics into bounded harness diagnostics. - Validate runtime-request origins against their strict durable shape and fall back from empty optional titles to a valid question prompt. - Reject invalid identities, projected-identity collisions, unstable semantic receipt identities, permission requests, and cross-turn projection fail closed. - Add integration coverage across reducer event families, correlation, identity validation, projected question resolution, and pinned-policy denial. - Document the durable projection boundary. - Do not change dependencies, lockfiles, workflows, runnerd selection, server behavior, UI, or migrations. ## Verification - Replay base: `80639f4f69c8938eb74bdc0833df93e0ed91dab3` (`master` after #12422 merged). - Exact replay head: `3cb29581d2bcbc4b47f8069baffd721c6ce4e444`. - Stable patch ID: `92910b56575e67ae83960177d467a565019ba282`. - The exact delta is 22 files, 1,206 additions, and 59 deletions, all in `packages/paperclip-runner`; it contains no lockfile, workflow, server, UI, dependency, or migration change. - `git diff --check` and the Cargo formatting check pass on the replayed delta. - Exact-head GitHub Actions run `33372209037` (attempt 2): **PASSED** with 23/23 jobs passed. - Greptile reviewed exact head `3cb29581d2bcbc4b47f8069baffd721c6ce4e444`: **5/5**, with zero unresolved review threads. - Superagent, contributor trust, Socket, and Snyk security checks: **PASSED**. - No local test result is claimed. GitHub Actions is the authoritative verification environment for this replayed revision. ## Risks - This function accepts reducer output, not raw sidecar frames. Callers must preserve the existing scope-first decode and reduction order. - Semantic input includes the already sanitized provider input while its content receipt uses the same canonical digest. - Structured input preserves the validated provider-neutral question set and sanitized origin. - Noncanonical provider request identities are deterministically projected for PRP while the original identity remains authoritative for the sidecar resolution command. - Existing PRP v1 identifiers remain schema-compatible; the only public ID-schema change widens turn/item limits from 160 to 240 characters. The internal ACPX sidecar wire schema now mirrors the stable IDs its Rust transport already enforced. - The projector verifies event-carried terminal and assistant turn identifiers against the durable context. - No production path invokes this projector in this pull request. Durable command execution remains the next slice. > 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 — check the roadmap first. See `CONTRIBUTING.md`. ## Model Used - OpenAI Codex with GPT-5.6, agentic reasoning, 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 linked the preceding public PR or described the issue in-PR - [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 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
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, andevent.schemaVersionare 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.
The files in fixtures/replay/golden/ are deterministic reducer oracles. Each
accepted replay fixture has a complete session snapshot and a compact parity
summary. pnpm generate:replay-goldens updates them after an intentional
reducer change; package build and CI fail when they drift.
The files in fixtures/local-runner/scripts/ drive the package-local fake
harness. They cover successful, failed, interrupted, interactive, duplicate
terminal, process-cleanup, and oversized-frame behavior without starting a
production adapter.