# AD-641a Build Report — Observability Bridge v1

**Prompt:** `prompts/ad-641a-observability-bridge.md`
**Builder:** Builder agent (Wave 9A, prompt 1 of 3)
**Date:** 2026-05-02
**Status:** ✅ Complete

## Files Changed

- `src/probos/events.py` (+2 lines) — 2 new EventTypes after MCP_BRIDGE_FAILED
- `src/probos/cognitive/observability/__init__.py` (+11) — new package init
- `src/probos/cognitive/observability/bridge.py` (+200) — new module
- `src/probos/config.py` (+9) — `ObservabilityBridgeConfig` + SystemConfig field
- `src/probos/startup/finalize.py` (+22) — startup wiring after MCP block
- `tests/test_ad641a_observability_bridge.py` (+200) — 14 new tests
- `PROGRESS.md`, `DECISIONS.md`, `docs/development/roadmap.md` — tracker updates

## Sections Implemented

- ✅ Section 0: Event Types
- ✅ Section 1: Package init
- ✅ Section 2: ObservabilityBridge + Snapshot
- ✅ Section 3: ObservabilityBridgeConfig + SystemConfig field
- ✅ Section 4: Startup wiring
- ✅ Section 5: 14 tests

## Post-Build Section Audit

Every `###` section in the prompt has corresponding code. No omissions.

## Test Results

- Focused (`-n 0`): 14/14 passed in 0.29s
- Adjacent (`tests/test_ad469_eps.py tests/test_unread_dms.py`): 21/21 passed
- Full gate (`-n 8 --dist=loadfile`): 10578 passed + 15 skipped + 1 environmental flake (`test_browse_threads_sort_recent` — passes serially per standing rule)

Test count delta: 10565 → 10579 (+14 new).

## Architect-Discretion Adjustments

`_publish_once` traps `create_post` exceptions internally and emits `OBSERVABILITY_BRIDGE_FAILED` so test 11 (direct `_publish_once` call per pass-1 N3) can observe the failed-emit without driving the loop. The outer `_publish_loop` exception handler remains as the second line of defense for any other exception path. No spec deviation — both behaviors are required by the test list.

## Deferred Nits

None.
