> For the complete documentation index, see [llms.txt](https://faction-os.gitbook.io/faction-os-docs/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://faction-os.gitbook.io/faction-os-docs/.spec_system/archive/sessions/phase18-session05-session-summary-engine-and-noise-filtering/implementation-notes.md).

# Implementation Notes

**Session ID**: `phase18-session05-session-summary-engine-and-noise-filtering` **Package**: apps/server **Started**: 2026-06-10 01:09 **Last Updated**: 2026-06-10 01:24

***

## Session Progress

| Metric              | Value   |
| ------------------- | ------- |
| Tasks Completed     | 23 / 23 |
| Estimated Remaining | 0 hours |
| Blockers            | 0       |

***

## Task Log

### 2026-06-10 - Session Start

**Environment verified**:

* [x] Prerequisites confirmed
* [x] Tools available
* [x] Directory structure ready
* [x] Package prerequisites confirmed for `apps/server`

***

### Task T001 - Verify Session 04 context helpers and session-end prerequisites

**Started**: 2026-06-10 01:09 **Completed**: 2026-06-10 01:09 **Duration**: 1 minute

**Notes**:

* Confirmed `buildIdleSuggestionContext` provides bounded mission prompt, mission summary, recent activity, safe modified-file extraction, and relative path sanitization.
* Confirmed `/event` completes missions on `hero_idle` and already triggers asynchronous idle generation after mission completion.
* Confirmed `SuggestionManager.setSessionSummary` exists and persists canonical `SessionSummary` state.

**Files Changed**:

* `.spec_system/specs/phase18-session05-session-summary-engine-and-noise-filtering/tasks.md` - marked T001 complete.
* `.spec_system/specs/phase18-session05-session-summary-engine-and-noise-filtering/implementation-notes.md` - recorded verification.

***

### Task T002 - Verify protocol summary and analysis contracts

**Started**: 2026-06-10 01:09 **Completed**: 2026-06-10 01:09 **Duration**: 1 minute

**Notes**:

* Confirmed `SessionSummary`, `SessionSummaryFollowUpTask`, and `SuggestionFollowUpCategory` are protocol-owned.
* Confirmed follow-up categories are `test`, `documentation`, `refactor`, and `validation`.
* Confirmed `AnalysisResult` and `AnalysisItem` parser paths are available for manager-level filtering.

**Files Changed**:

* `.spec_system/specs/phase18-session05-session-summary-engine-and-noise-filtering/tasks.md` - marked T002 complete.
* `.spec_system/specs/phase18-session05-session-summary-engine-and-noise-filtering/implementation-notes.md` - recorded protocol verification.

***

### Task T003 - Verify SuggestionManager state and broadcast prerequisites

**Started**: 2026-06-10 01:09 **Completed**: 2026-06-10 01:09 **Duration**: 1 minute

**Notes**:

* Confirmed `setSessionSummary` parses protocol summaries, replaces summaries by session, persists state, and rolls back failed mutations.
* Confirmed `setAnalysisResult` is the correct store-time filtering point.
* Confirmed `normalizeStore` is the correct load-time filtering point, and `emitSuggestionMutationUpdate` is the canonical snapshot broadcast path.

**Files Changed**:

* `.spec_system/specs/phase18-session05-session-summary-engine-and-noise-filtering/tasks.md` - marked T003 complete.
* `.spec_system/specs/phase18-session05-session-summary-engine-and-noise-filtering/implementation-notes.md` - recorded manager verification.

***

### Task T004 - Create analysis noise filter helpers

**Started**: 2026-06-10 01:10 **Completed**: 2026-06-10 01:10 **Duration**: 1 minute

**Notes**:

* Added pure predicates that parse analysis-shaped items through protocol validation before filtering.
* Added explicit rejection reasons for truncated context, unreadable context, missing context, partial file, and invalid analysis item cases.

**Files Changed**:

* `apps/server/src/lib/analysisNoiseFilter.ts` - created filter predicates, result helpers, and result-level filtering.
* `.spec_system/specs/phase18-session05-session-summary-engine-and-noise-filtering/tasks.md` - marked T004 complete.
* `.spec_system/specs/phase18-session05-session-summary-engine-and-noise-filtering/implementation-notes.md` - recorded implementation notes.

**BQC Fixes**:

* Trust boundary enforcement: analysis items are protocol-parsed before predicate decisions.

***

### Task T005 - Create session summary prompt

**Started**: 2026-06-10 01:10 **Completed**: 2026-06-10 01:10 **Duration**: 1 minute

**Notes**:

* Added the maintained session summary system prompt with exact follow-up categories.
* Prompt requires one or two follow-up tasks, JSON-only output, and no raw prompts, command bodies, terminal output, provider payloads, secrets, transcript contents, absolute paths, or private URLs.

**Files Changed**:

* `apps/server/src/llm/prompts/session-summary-engine.md` - created auditable prompt file.
* `.spec_system/specs/phase18-session05-session-summary-engine-and-noise-filtering/tasks.md` - marked T005 complete.
* `.spec_system/specs/phase18-session05-session-summary-engine-and-noise-filtering/implementation-notes.md` - recorded implementation notes.

**BQC Fixes**:

* Error information boundaries: prompt rules explicitly block unsafe persisted or emitted content.

***

### Task T006 - Register session summary prompt

**Started**: 2026-06-10 01:10 **Completed**: 2026-06-10 01:10 **Duration**: 1 minute

**Notes**:

* Added `sessionSummaryEngine` to the maintained prompt registry.
* Preserved existing prompt keys for plan, idle suggestion, transcript, analysis, and auto-improver engines.

**Files Changed**:

* `apps/server/src/llm/prompts/index.ts` - registered the new prompt key and updated the registry comment.
* `.spec_system/specs/phase18-session05-session-summary-engine-and-noise-filtering/tasks.md` - marked T006 complete.
* `.spec_system/specs/phase18-session05-session-summary-engine-and-noise-filtering/implementation-notes.md` - recorded implementation notes.

***

### Task T007 - Create session summary engine parser and normalizer

**Started**: 2026-06-10 01:10 **Completed**: 2026-06-10 01:10 **Duration**: 1 minute

**Notes**:

* Added engine input/options types and a `generateSessionSummary` boundary using the existing LLM client.
* Added response parsing for direct JSON, fenced JSON, extracted arrays, and extracted objects.
* Added follow-up task normalization with protocol category validation and max-two output.

**Files Changed**:

* `apps/server/src/llm/engines/sessionSummaryEngine.ts` - created engine parser, normalizer, and generator.
* `.spec_system/specs/phase18-session05-session-summary-engine-and-noise-filtering/tasks.md` - marked T007 complete.
* `.spec_system/specs/phase18-session05-session-summary-engine-and-noise-filtering/implementation-notes.md` - recorded implementation notes.

**BQC Fixes**:

* Contract alignment: normalized output is passed through `parseSessionSummary` before it can be returned to lifecycle code.

***

### Task T008 - Create deterministic summary fallback builder

**Started**: 2026-06-10 01:10 **Completed**: 2026-06-10 01:10 **Duration**: 1 minute

**Notes**:

* Added fallback summaries for file-hint validation, test follow-up, and recent activity validation.
* Fallback IDs are deterministic hashes over safe session and task context, and fallback summaries are protocol-validated.

**Files Changed**:

* `apps/server/src/llm/engines/sessionSummaryEngine.ts` - added fallback summary builder and safe modified-file handling.
* `.spec_system/specs/phase18-session05-session-summary-engine-and-noise-filtering/tasks.md` - marked T008 complete.
* `.spec_system/specs/phase18-session05-session-summary-engine-and-noise-filtering/implementation-notes.md` - recorded implementation notes.

**BQC Fixes**:

* External dependency resilience: malformed, empty, or unavailable provider output falls back to schema-valid local output when safe context exists.

***

### Task T009 - Create summary lifecycle coordinator shell

**Started**: 2026-06-10 01:10 **Completed**: 2026-06-10 01:10 **Duration**: 1 minute

**Notes**:

* Added lifecycle coordinator options for manager, broadcaster, generator injection, clock injection, timeout, project root, recent activity cap, and logger.
* Added in-flight generation records with abort controllers and timeout handles.
* Added destroy cleanup that aborts in-flight generation, clears timers, and clears retained recent activity.

**Files Changed**:

* `apps/server/src/lib/sessionSummaryLifecycle.ts` - created coordinator shell and cleanup contract.
* `.spec_system/specs/phase18-session05-session-summary-engine-and-noise-filtering/tasks.md` - marked T009 complete.
* `.spec_system/specs/phase18-session05-session-summary-engine-and-noise-filtering/implementation-notes.md` - recorded implementation notes.

**BQC Fixes**:

* Resource cleanup: destroy clears timeout handles, aborts in-flight work, and releases retained maps.

***

### Task T010 - Implement stable session keyed trigger and duplicate suppression

**Started**: 2026-06-10 01:10 **Completed**: 2026-06-10 01:10 **Duration**: 1 minute

**Notes**:

* Added `handleSessionCompleted` with context resolution through the Session 04 context builder.
* Added a per-session in-flight map keyed by stable session ID.
* Duplicate completed-session triggers return `in_flight` without starting another generation.

**Files Changed**:

* `apps/server/src/lib/sessionSummaryLifecycle.ts` - implemented trigger and in-flight guard.
* `.spec_system/specs/phase18-session05-session-summary-engine-and-noise-filtering/tasks.md` - marked T010 complete.
* `.spec_system/specs/phase18-session05-session-summary-engine-and-noise-filtering/implementation-notes.md` - recorded implementation notes.

**BQC Fixes**:

* Duplicate action prevention: concurrent generation for the same session is suppressed.

***

### Task T011 - Implement timeout, abort, late suppression, and compact warnings

**Started**: 2026-06-10 01:10 **Completed**: 2026-06-10 01:10 **Duration**: 1 minute

**Notes**:

* Added a 15-second default timeout that aborts the generation signal.
* Suppressed late writes after destroy or stale generation token changes.
* Added compact warning logs containing only reason, session ID, and hero ID.

**Files Changed**:

* `apps/server/src/lib/sessionSummaryLifecycle.ts` - implemented timeout and warning behavior.
* `.spec_system/specs/phase18-session05-session-summary-engine-and-noise-filtering/tasks.md` - marked T011 complete.
* `.spec_system/specs/phase18-session05-session-summary-engine-and-noise-filtering/implementation-notes.md` - recorded implementation notes.

**BQC Fixes**:

* External dependency resilience: generation is bounded by timeout and local fallback.
* Error information boundaries: warning logs do not include provider payloads, prompts, paths, or transcripts.

***

### Task T012 - Implement manager write and broadcast path

**Started**: 2026-06-10 01:10 **Completed**: 2026-06-10 01:10 **Duration**: 1 minute

**Notes**:

* Summary persistence goes through `SuggestionManager.setSessionSummary`.
* Successful writes emit `emitSuggestionMutationUpdate` so summary updates use the canonical `suggestion_update` snapshot path.
* Equivalent existing summaries are treated as idempotent no-ops, and manager failures return `manager_error`.

**Files Changed**:

* `apps/server/src/lib/sessionSummaryLifecycle.ts` - implemented manager write, broadcast, idempotency, and failure handling.
* `.spec_system/specs/phase18-session05-session-summary-engine-and-noise-filtering/tasks.md` - marked T012 complete.
* `.spec_system/specs/phase18-session05-session-summary-engine-and-noise-filtering/implementation-notes.md` - recorded implementation notes.

**BQC Fixes**:

* Failure path completeness: manager write errors are caught, logged compactly, and reported through lifecycle result state.
* Contract alignment: persisted summaries enter state only through `SuggestionManager`.

***

### Task T013 - Wire summary lifecycle in server runtime

**Started**: 2026-06-10 01:11 **Completed**: 2026-06-10 01:11 **Duration**: 1 minute

**Notes**:

* Instantiated `SessionSummaryLifecycleCoordinator` with the shared suggestion manager, broadcaster, project root, and logger.
* Injected the coordinator into root and `/api` event routes.
* Destroy order now aborts summary generation before idle generation and manager shutdown.

**Files Changed**:

* `apps/server/src/server.ts` - wired construction, route injection, and shutdown cleanup.
* `.spec_system/specs/phase18-session05-session-summary-engine-and-noise-filtering/tasks.md` - marked T013 complete.
* `.spec_system/specs/phase18-session05-session-summary-engine-and-noise-filtering/implementation-notes.md` - recorded implementation notes.

**BQC Fixes**:

* Resource cleanup: runtime shutdown destroys summary generation before manager teardown.

***

### Task T014 - Wire non-blocking event-route summary generation

**Started**: 2026-06-10 01:11 **Completed**: 2026-06-10 01:11 **Duration**: 1 minute

**Notes**:

* Added `sessionSummaries` as an optional event router dependency.
* Triggered summary generation after mission completion on `hero_idle` while leaving the HTTP response path non-blocking.
* Reused the existing lifecycle activity recorder so summary context receives bounded recent activity.

**Files Changed**:

* `apps/server/src/routes/event.ts` - wired non-blocking summary generation and activity recording.
* `.spec_system/specs/phase18-session05-session-summary-engine-and-noise-filtering/tasks.md` - marked T014 complete.
* `.spec_system/specs/phase18-session05-session-summary-engine-and-noise-filtering/implementation-notes.md` - recorded implementation notes.

**BQC Fixes**:

* Failure path completeness: async generation failures emit a compact warning toast without failing `/event`.

***

### Task T015 - Apply store-time analysis noise filtering

**Started**: 2026-06-10 01:11 **Completed**: 2026-06-10 01:11 **Duration**: 1 minute

**Notes**:

* `SuggestionManager.setAnalysisResult` now protocol-parses input, filters noisy items, and stores only the filtered result.
* Null analysis results are still preserved as explicit clears.

**Files Changed**:

* `apps/server/src/managers/suggestionManager.ts` - applied store-time noise filtering.
* `.spec_system/specs/phase18-session05-session-summary-engine-and-noise-filtering/tasks.md` - marked T015 complete.
* `.spec_system/specs/phase18-session05-session-summary-engine-and-noise-filtering/implementation-notes.md` - recorded implementation notes.

**BQC Fixes**:

* Trust boundary enforcement: analysis state is validated and filtered before mutation.

***

### Task T016 - Apply load-time analysis noise filtering

**Started**: 2026-06-10 01:11 **Completed**: 2026-06-10 01:11 **Duration**: 1 minute

**Notes**:

* `normalizeStore` now filters persisted analysis results during manager load.
* Load detects filtered analysis item changes and marks the store mutated so cleaned state is persisted through the normal local save path.

**Files Changed**:

* `apps/server/src/managers/suggestionManager.ts` - applied load-time filtering and dirty-store detection.
* `.spec_system/specs/phase18-session05-session-summary-engine-and-noise-filtering/tasks.md` - marked T016 complete.
* `.spec_system/specs/phase18-session05-session-summary-engine-and-noise-filtering/implementation-notes.md` - recorded implementation notes.

**BQC Fixes**:

* State freshness on re-entry: persisted noisy analysis entries are revalidated on manager startup.

***

### Task T017 - Update server README

**Started**: 2026-06-10 01:11 **Completed**: 2026-06-10 01:11 **Duration**: 1 minute

**Notes**:

* Documented server-side session summaries, timeout, duplicate suppression, provider opt-in, and fallback behavior.
* Documented analysis noise filtering at store time and load time.
* Updated remaining Phase 18 deferrals so implemented summary/filter behavior is no longer described as future work.

**Files Changed**:

* `apps/server/README_server.md` - updated Quest Board Suggestion Manager documentation.
* `.spec_system/specs/phase18-session05-session-summary-engine-and-noise-filtering/tasks.md` - marked T017 complete.
* `.spec_system/specs/phase18-session05-session-summary-engine-and-noise-filtering/implementation-notes.md` - recorded implementation notes.

***

### Task T018 - Keep summary lifecycle logs compact and redacted

**Started**: 2026-06-10 01:11 **Completed**: 2026-06-10 01:11 **Duration**: 1 minute

**Notes**:

* Summary generation warnings include stable status labels plus session and hero IDs only.
* Manager write warnings include only error class, session ID, and hero ID.
* Analysis filtering does not log filtered item content.

**Files Changed**:

* `apps/server/src/lib/sessionSummaryLifecycle.ts` - implemented compact warning paths.
* `apps/server/src/managers/suggestionManager.ts` - filtering runs without content logging.
* `.spec_system/specs/phase18-session05-session-summary-engine-and-noise-filtering/tasks.md` - marked T018 complete.
* `.spec_system/specs/phase18-session05-session-summary-engine-and-noise-filtering/implementation-notes.md` - recorded implementation notes.

**BQC Fixes**:

* Error information boundaries: logs do not include raw paths, prompts, transcripts, provider payloads, or secrets.

***

### Task T019 - Write session summary engine tests

**Started**: 2026-06-10 01:12 **Completed**: 2026-06-10 01:23 **Duration**: 11 minutes

**Notes**:

* Added parser tests for object, fenced JSON, and extracted array shapes.
* Added category validation, max-two cap, deterministic fallback, malformed output, provider failure, and empty-context coverage.
* Focused Vitest run passed after adjusting fallback assertions to account for the valid two-task fallback.

**Files Changed**:

* `apps/server/tests/sessionSummaryEngine.test.ts` - created focused engine tests.
* `apps/server/src/llm/engines/sessionSummaryEngine.ts` - tightened provider failure fallback behavior.
* `.spec_system/specs/phase18-session05-session-summary-engine-and-noise-filtering/tasks.md` - marked T019 complete.
* `.spec_system/specs/phase18-session05-session-summary-engine-and-noise-filtering/implementation-notes.md` - recorded implementation notes.

**BQC Fixes**:

* External dependency resilience: injected provider failures now fall back locally in the engine.

***

### Task T020 - Write analysis noise filter tests

**Started**: 2026-06-10 01:12 **Completed**: 2026-06-10 01:23 **Duration**: 11 minutes

**Notes**:

* Added rejection coverage for truncated, unreadable, missing, and partial context self-talk phrases.
* Added valid concrete-item acceptance and invalid analysis-shaped input coverage.
* Focused Vitest run passed.

**Files Changed**:

* `apps/server/tests/analysisNoiseFilter.test.ts` - created focused noise filter tests.
* `.spec_system/specs/phase18-session05-session-summary-engine-and-noise-filtering/tasks.md` - marked T020 complete.
* `.spec_system/specs/phase18-session05-session-summary-engine-and-noise-filtering/implementation-notes.md` - recorded implementation notes.

***

### Task T021 - Write session summary lifecycle tests

**Started**: 2026-06-10 01:12 **Completed**: 2026-06-10 01:23 **Duration**: 11 minutes

**Notes**:

* Added lifecycle tests for summary generation, manager write, canonical `suggestion_update` broadcast, duplicate in-flight suppression, timeout fallback, destroy cleanup, and warning behavior.
* Focused Vitest run passed.

**Files Changed**:

* `apps/server/tests/sessionSummaryLifecycle.test.ts` - created focused lifecycle tests.
* `.spec_system/specs/phase18-session05-session-summary-engine-and-noise-filtering/tasks.md` - marked T021 complete.
* `.spec_system/specs/phase18-session05-session-summary-engine-and-noise-filtering/implementation-notes.md` - recorded implementation notes.

**BQC Fixes**:

* Resource cleanup: destroy test verifies abort and timer cleanup.
* Duplicate action prevention: duplicate trigger test verifies in-flight suppression.

***

### Task T022 - Write SuggestionManager filtering tests

**Started**: 2026-06-10 01:12 **Completed**: 2026-06-10 01:23 **Duration**: 11 minutes

**Notes**:

* Added store-time filtering coverage for valid plus noisy analysis items.
* Added load-time filtering coverage that writes a mixed persisted store, verifies valid state survives, and verifies cleaned persistence is rewritten.
* Focused Vitest run passed.

**Files Changed**:

* `apps/server/tests/suggestionManager.test.ts` - added analysis filtering tests.
* `.spec_system/specs/phase18-session05-session-summary-engine-and-noise-filtering/tasks.md` - marked T022 complete.
* `.spec_system/specs/phase18-session05-session-summary-engine-and-noise-filtering/implementation-notes.md` - recorded implementation notes.

**BQC Fixes**:

* State freshness on re-entry: load-time test verifies stale noisy persisted analysis is removed on startup.

***

### Task T023 - Write route integration coverage and run verification

**Started**: 2026-06-10 01:12 **Completed**: 2026-06-10 01:24 **Duration**: 12 minutes

**Notes**:

* Added route integration coverage for completed event-ingested sessions reaching `SuggestionManager` session summary state.
* Ran focused server Vitest files covering summary engine, noise filter, summary lifecycle, manager filtering, and route integration.
* Ran server typecheck and ASCII/LF validation for all session artifacts.

**Files Changed**:

* `apps/server/tests/routes.test.ts` - added session summary route integration coverage.
* `.spec_system/specs/phase18-session05-session-summary-engine-and-noise-filtering/tasks.md` - marked T023 and completion checklist complete.
* `.spec_system/specs/phase18-session05-session-summary-engine-and-noise-filtering/implementation-notes.md` - recorded final verification.

**BQC Fixes**:

* Contract alignment: route integration test verifies completed sessions produce typed `SessionSummary` manager state.

***

## Verification

* `npx vitest run apps/server/tests/sessionSummaryEngine.test.ts apps/server/tests/analysisNoiseFilter.test.ts apps/server/tests/sessionSummaryLifecycle.test.ts apps/server/tests/suggestionManager.test.ts apps/server/tests/routes.test.ts` - passed, 35 tests.
* `npm --workspace apps/server run typecheck` - passed.
* ASCII and LF validation for session artifacts - passed.

***


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