# Phase 165.5-03 Brain Bridge Summary

Status: implemented in working tree

## Goal

Close the next `165.5-03 / 999.84` slice by giving the repo-local concept-graph
export an explicit, receipt-backed bridge into the external
theoretical-physics brain instead of leaving that handoff implicit.

## What Landed

- new support module:
  - `knowledge_hub/obsidian_graph_bridge_support.py`
- new explicit sync surface:
  - `sync_concept_graph_export_to_theoretical_physics_brain(...)`
- new service wrapper:
  - `AITPService.sync_l1_graph_export_to_theoretical_physics_brain(...)`
- bridge behavior:
  - resolves the theoretical-physics brain root from explicit target,
    environment override, configured backend card, or repo-local fallback
  - mirrors the repo-local concept-graph export into:
    - `<brain-root>/90 AITP Imports/concept-graphs/<topic_slug>/`
  - writes a durable local receipt:
    - `intake/topics/<topic_slug>/vault/wiki/concept-graph/theoretical_physics_brain_sync.receipt.json`
- the bridge is explicit and side-effectful by design:
  - it does not run during ordinary `status` materialization
  - it remains a separate sync action with an auditable receipt
- isolated acceptance now exists for the end-to-end path:
  - `runtime/scripts/run_l1_graph_obsidian_brain_bridge_acceptance.py`

## Verification

- `python -m pytest research/knowledge-hub/tests/test_obsidian_graph_export.py -q`
- `python -m pytest research/knowledge-hub/tests/test_obsidian_graph_bridge_support.py -q`
- `python -m pytest research/knowledge-hub/tests/test_runtime_scripts.py -q -k "obsidian_export or multicommunity or brain_bridge"`
- `python -m pytest research/knowledge-hub/tests/test_aitp_service.py -q -k "l1_vault or concept_graph or sync_l1_graph_export_to_theoretical_physics_brain"`
- `python research/knowledge-hub/runtime/scripts/run_l1_graph_obsidian_brain_bridge_acceptance.py --json`

## Outcome

`165.5-03` now has an explicit external bridge slice:

- the repo-local `L1` concept-graph export can now be mirrored into the
  operator-primary theoretical-physics brain without hiding the writeback
- the bridge stays honest about side effects through a local receipt artifact
- paired-backend semantics are respected: this is an explicit sync surface, not
  a silent promotion or consultation shortcut

## Remaining Open Work Inside 165.5-03 / 999.84

- decide whether this explicit bridge now closes `165.5-03`, or whether a
  follow-up CLI entrypoint is still required for operator ergonomics
- optional later enrichment:
  - markdown receipt note alongside the JSON receipt
  - selective sync instead of full mirror replacement
