# AD-641f Build Report — Engineering Chief Observability v1

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

## Files Changed

- `src/probos/events.py` (+1) — 1 new EventType
- `src/probos/cognitive/engineering_sensors/__init__.py` (+8)
- `src/probos/cognitive/engineering_sensors/bundle.py` (+13)
- `src/probos/cognitive/engineering_sensors/service.py` (+135)
- `src/probos/config.py` (+9) — `EngineeringSensorsConfig` + SystemConfig field
- `src/probos/startup/finalize.py` (+22) — startup wiring
- `tests/test_ad641f_engineering_sensors.py` (+170) — 13 new tests
- `PROGRESS.md`, `DECISIONS.md`, `docs/development/roadmap.md` — tracker updates

## Sections Implemented

- ✅ Section 0: Event Types
- ✅ Section 1: Package init
- ✅ Section 2: EngineeringSensorBundle
- ✅ Section 3: EngineeringSensorService
- ✅ Section 4: EngineeringSensorsConfig
- ✅ Section 5: Startup wiring
- ✅ Section 6: 13 tests

## Post-Build Section Audit

Every `###` section in the prompt has corresponding code. No omissions. Capability registry flattening verified to use `cap.can` per pass-1 R1.

## Test Results

- Focused (`-n 0`): 13/13 passed in 0.27s
- Full gate (`-n 8 --dist=loadfile`): **10603 passed + 15 skipped**, no failures

Test count delta: 10590 → 10603 (+13 new).

## Deferred Nits

None.
