---
id: TAMQ-WP-0002
type: workplan
title: "Coordination-engine adapter boundary"
domain: communication
repo: tmux-amq
status: finished
owner: codex
topic_slug: coulomb-social
created: "2026-08-24"
updated: "2026-08-26"
state_hub_workstream_id: "48da5fa7-b7bf-5d13-8edc-b90f266e241c"
---

# Coordination-engine adapter boundary

Connect coordination-engine to tmux-amq through the existing local Unix-socket
boundary while preserving tmux-amq's local transport authority and keeping
workflow/orchestration policy in coordination-engine.

## Specify the adapter contract

```task
id: TAMQ-WP-0002-T01
status: done
priority: high
state_hub_task_id: "a222dab7-edea-58c6-9dab-d684eb65c412"
```

Define request, response, identity, delivery, acknowledgement, retry, and
failure semantics for a coordination-engine client. Resolve protocol-version
negotiation and document which system owns each state transition.

The implemented contract is `spec/coordination-engine-adapter-v0.1.md`. It
defines same-user socket authentication, major-version and capability
negotiation, exact endpoint resolution, message/correlation identity,
idempotency conflicts, bounded delivery states, ack timeouts, late
acknowledgement, recovery, and the TAMQ/coordination ownership boundary.

## Implement the coordination-engine client adapter

```task
id: TAMQ-WP-0002-T02
status: done
priority: high
state_hub_task_id: "195db613-05a3-58d8-9e94-2db34920576f"
```

Implement the adapter against the stable socket contract without importing
tmux/control-mode concerns into coordination-engine. This task waits for T01.

`tamq.client` provides a transport-only async client and
`CoordinationEngineAdapter`. It opens a fresh socket connection per operation,
resolves one live repository endpoint, maps the coordination lease ID to a
durable idempotency key, preserves trigger correlation metadata, and exposes
receipt, acknowledgement, and terminal retry operations. Protocol constants
are separate from the service and terminal implementation.

## Prove interoperability and recovery

```task
id: TAMQ-WP-0002-T03
status: done
priority: high
state_hub_task_id: "23c7f6c7-be48-5b6c-b85c-ae05d82cc277"
```

Add end-to-end coverage for delivery, acknowledgement, reconnect, replay,
deduplication, incompatible protocol versions, and endpoint disappearance.
Update both repositories' operator documentation with the verified workflow.

Unix-socket integration tests cover negotiation, identical-wake deduplication,
idempotency conflict, durable receipt recovery after service restart,
incompatible protocol, and disappeared endpoints. Reliability tests cover
delivery, explicit and late acknowledgement, same-ID ack-timeout redelivery,
lease expiry, exhaustion, and retry reset. JSONL replay now uses deterministic
idempotency while retaining normal gita validation. TAMQ documentation and the
coordination-engine worker-service specification link the verified contract.

## Residuals

This workplan does not implement coordination-engine's trigger observer,
coordination leases, actionability decisions, checkpoints, or State Hub
projection. Those remain owned by `COORDINATION-WP-0003` and consume this
adapter rather than expanding TAMQ's scope.