Summary

Describe the problem and fix in 2–5 bullets:

• Problem: post-compaction session-memory index sync was not executed from the compact runner, leaving session memory potentially stale.
• Why it matters: memory search freshness after compaction directly affects follow-up retrieval quality.
• What changed: implemented post-compaction sync with mode handling (off|async|await), session-agent resolution, memory config checks, and warning-only fallbacks.
• What did NOT change (scope boundary): no broader memory backend redesign.

Change Type (select all)

• Bug fix
• Feature
• Refactor
• 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 [Bug]: Compaction summarization does not preserve exact identifiers #19207
• Related (fix): Compaction: preserve recent context and sync session memory post-compact #20038, Compaction Runner: add post-sync mode scaffold #25560

User-visible / Behavior Changes

• After successful compaction, session-memory index sync can run immediately based on agents.defaults.compaction.postIndexSync and agents.defaults.memorySearch.sync.sessions.postCompactionForce.

Security Impact (required)

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

Repro + Verification

Environment

• OS: macOS
• Runtime/container: Node 22 + pnpm
• Model/provider: n/a (unit/integration tests)
• Integration/channel (if any): n/a
• Relevant config (redacted): compaction + memorySearch defaults

Steps

1. pnpm vitest run src/agents/pi-embedded-runner/run.overflow-compaction.test.ts src/auto-reply/reply/post-compaction-context.test.ts src/agents/memory-search.test.ts
2. pnpm vitest run src/agents/compaction.retry.test.ts src/agents/compaction.identifier-preservation.test.ts src/memory/index.test.ts src/memory/manager.atomic-reindex.test.ts src/memory/manager.async-search.test.ts src/memory/manager.watcher-config.test.ts src/auto-reply/reply/followup-runner.test.ts src/auto-reply/reply/agent-runner.runreplyagent.test.ts src/auto-reply/reply/commands.test.ts src/auto-reply/reply/agent-runner.misc.runreplyagent.test.ts
3. pnpm tsgo

Expected

• Targeted compaction/memory/reply suites pass and typecheck remains clean.

Actual

• Local targeted suites passed (13 files / 155 tests) and pnpm tsgo passed.

Evidence

Attach at least one:

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

Human Verification (required)

What you personally verified (not just CI), and how:

• Verified scenarios: transcript updates are emitted post-compaction; memory sync path executes with mode-aware behavior and safe fallbacks.
• Edge cases checked: off mode bypass, missing manager/sync method, async-mode warning handling.
• What you did not verify: full pnpm test matrix and long-lived production deployments.

Compatibility / Migration

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

Failure Recovery (if this breaks)

• How to disable/revert this change quickly:
  • Set agents.defaults.compaction.postIndexSync: "off"
  • Or revert this PR
• Files/config to restore: src/agents/pi-embedded-runner/compact.ts
• Known bad symptoms reviewers should watch for: compaction latency increase in await mode.

Risks and Mitigations

List only real risks for this PR. Add/remove entries as needed. If none, write None.

• Risk: await mode can add latency immediately after compaction.
  • Mitigation: default mode is async; off and async remain available.
• Risk: sync failures could surface as noisy warnings.
  • Mitigation: failures are warning-only and compaction success path remains intact.

Stack: 9/9, depends on #25560.