Summary

• CI pipeline: checks-node-agentic
• Failing problem: src/agents/pi-embedded-runner/run.timeout-triggered-compaction.test.ts -> fires compaction hooks during timeout recovery for ownsCompaction engines
• Problem: the shared overflow-compaction harness still mocked ./compact.js after run.ts switched to importing runPostCompactionSideEffects from ./compaction-hooks.js
• Why it matters: timeout-recovery coverage for owns-compaction engines started failing even though runtime behavior was still calling the side-effect seam
• What changed: mock the current ./compaction-hooks.js seam in the shared harness while keeping the existing ./compact.js mock for compatibility
• What did NOT change (scope boundary): runtime compaction behavior, hook execution order, and non-agent surfaces

Change Type (select all)

• Bug fix
• Feature
• Refactor required for the fix
• Docs
• Security hardening
• Chore/infra

Scope (select all touched areas)

• Gateway / orchestration
• Skills / tool execution
• Auth / tokens
• Memory / storage
• Integrations
• API / contracts
• UI / DX
• CI/CD / infra

Linked Issue/PR

• Closes #
• Related Plugins: keep untrusted workspace channel shadows out of setup-time loads #64154
• This PR fixes a bug or regression

Root Cause (if applicable)

• Root cause: the test harness mocked the old barrel seam after src/agents/pi-embedded-runner/run.ts started importing runPostCompactionSideEffects directly from src/agents/pi-embedded-runner/compaction-hooks.ts
• Missing detection / guardrail: the shared harness did not keep its mocked module path aligned with the runtime import boundary
• Contributing context (if known): overflow and timeout recovery share the same harness, so the stale mock only showed up once a test asserted the post-compaction side-effect call directly

Regression Test Plan (if applicable)

• Coverage level that should have caught this:
  • Unit test
  • Seam / integration test
  • End-to-end test
  • Existing coverage already sufficient
• Target test or file: src/agents/pi-embedded-runner/run.timeout-triggered-compaction.test.ts
• Scenario the test should lock in: owns-compaction timeout recovery fires post-compaction side effects through the same runtime seam that run.ts imports
• Why this is the smallest reliable guardrail: the failure came from the shared mock boundary rather than the core timeout-recovery logic itself
• Existing test that already covers this (if any): src/agents/pi-embedded-runner/run.overflow-compaction.test.ts exercises the same harness for overflow recovery
• If no new test is added, why not: existing targeted coverage was sufficient once the harness mocked the right seam

User-visible / Behavior Changes

None.

Diagram (if applicable)

N/A

Before:
run.ts -> compaction-hooks.ts -> side effects
harness -> mocks compact.ts only
=> timeout recovery assertion misses the real call site

After:
run.ts -> compaction-hooks.ts -> mocked side effects seam
harness -> mocks compaction-hooks.ts (and keeps compact.ts compatibility mock)
=> timeout recovery assertion observes the runtime call path

Security Impact (required)

• New permissions/capabilities? (Yes/No) No
• Secrets/tokens handling changed? (Yes/No) No
• New/changed network calls? (Yes/No) No
• Command/tool execution surface changed? (Yes/No) No
• Data access scope changed? (Yes/No) No
• If any Yes, explain risk + mitigation:

Repro + Verification

Environment

• OS: Linux
• Runtime/container: Node 22 / pnpm workspace
• Model/provider: N/A
• Integration/channel (if any): N/A
• Relevant config (redacted): default test harness config

Steps

1. Run pnpm test src/agents/pi-embedded-runner/run.timeout-triggered-compaction.test.ts src/agents/pi-embedded-runner/run.overflow-compaction.test.ts
2. Observe timeout-recovery owns-compaction coverage
3. Confirm both timeout and overflow compaction suites pass

Expected

• The timeout-recovery test sees runPostCompactionSideEffects invoked through the current runtime seam.

Actual

• Before this change, the timeout-recovery test failed because the harness mocked the wrong module path.

Evidence

Attach at least one:

• Failing test/log before + passing after
• Trace/log snippets
• Screenshot/recording
• Perf numbers (if relevant)

Human Verification (required)

• Verified scenarios: timeout-triggered compaction and overflow compaction both pass with the shared harness after mocking ./compaction-hooks.js
• Edge cases checked: kept the legacy ./compact.js mock in place so older callers remain covered by the same harness
• What you did not verify: full repo-wide agent/contract suites

Review Conversations

• I replied to or resolved every bot review conversation I addressed in this PR.
• I left unresolved only the conversations that still need reviewer or maintainer judgment.

Compatibility / Migration

• Backward compatible? (Yes/No) Yes
• Config/env changes? (Yes/No) No
• Migration needed? (Yes/No) No
• If yes, exact upgrade steps:

Risks and Mitigations

• Risk: another harness or test could drift from the runtime import seam in the future
  • Mitigation: this shared harness now mocks both the legacy barrel and the runtime seam used by run.ts