[Epic] Coordination primitives — delegate goals, not one-shots (Coder as first consumer)

[serge-ivo]

Make agent coordination correct — as a platform primitive Coder is the first consumer of, NOT a refactor of Coder's hardcoded internals. Design: docs/coordination-primitives.md. Companion to agent-platform-strategy.md + connector-manifest.md (#143).

Problem (verified): the Overseer (drive_claude) and send_to_cli are fire-and-forget one-shots — no follow-through, no typed task/status, three overlapping drive-paths, and the console Loop is client-driven (dies when the tab closes) while the durable Pilot (CodingSessionWorkflow) overlaps it.

What stays (best practice, keep): Engine=executor / brain=decider; deterministic target routing (repo → one active session → live node); per-instance isolation; declarative consent-gated tools. This is not a rewrite — only the coordination policy on top changes.

Principle: delegate at the right abstraction, through a durable handoff. Commands → Engines; goals → autonomous workers (Pilot, later another agent) that own loop/retry/escalate; the coordinator delegates goals and tracks status.

We build ONE thing now (the fix as the primitive) and defer the generalizations until they have a proven primitive and/or a real second consumer — avoiding both "polish the hardcoded thing" and "build the framework too early."

• Near-term (build): [coordination] Overseer delegates a GOAL to the durable Pilot (replace the one-shot) #155 Overseer delegates a goal → durable Pilot (+ task/status handle), replacing the one-shot for multi-step.
• Deferred (filed): first-class delegate primitive ([coordination][deferred] First-class delegate(target, goal) registry primitive #156) · typed task/handoff model ([coordination][deferred] Typed task/handoff model (owner/status/result) #157) · converge Loop into the durable Pilot ([coordination] Platform-provided durable agent loop — the Loop is an agent-level primitive, not a browser poll #158) · cross-agent delegation ([coordination][deferred] Cross-agent delegation (delegate a goal to another instance's brain) #159) · retire the workflow enum ([coordination][deferred] Retire the workflow closed enum → declarative behavior #160).

[serge-ivo]

Near-term build #155 shipped (1a8c40d): Overseer → durable Pilot goal delegation + observable task. The epic's substrate is now proven with Coder as first consumer. Remaining are the deferred generalizations: #156 (first-class delegate verb), #157 (typed task model), #158 (Loop→Pilot convergence), #159 (cross-agent), #160 (retire workflow enum — now a convergence job per its updated note).

[serge-ivo]

Status update 2026-08-04 — the deferral gate is met

Near-term #155 (Overseer delegates a GOAL to the durable Pilot) is closed and shipped — delegateGoal + the board task record in routes/coding.ts / lib/delegation.ts.

The sequencing note said: "THEN cross-agent + workflow-enum retirement once a second consumer exists." That consumer has arrived — configurable multi-layer supervision, where a user wires agents to oversee other agents at arbitrary depth, as configuration rather than code.

New design: docs/supervision.md, which carries #154's reasoning one level up. The same argument this epic made about delegate applies to the hierarchy itself: Coder's Overseer → Pilot → Engine structure is correct, but it lives inside the agent. Three things hardcode it — the target type (drive_claude(repoId, …)), the coordinator being a route, and depth being fixed at 2 by construction. No table describes who supervises whom, so supervision cannot be configured, inspected, or reused.

Un-deferred: #156 (generalize the delegate target — the smallest useful step, everything depends on it) and #159 (cross-agent, which should now fall out rather than be built directly).

New children, covering hazards that only appear once hierarchy is configurable rather than written by a human:

• [coordination] Supervision graph as configured platform data — hierarchy belongs to the platform, not inside an agent #183 — supervision graph as configured data (edge table, DAG validation, reuses the 0058 delivery outbox)
• [coordination] Autonomous work budget — bound spend across every unattended entry point #184 — delegation budget: depth + spend flow DOWN the tree (fan-out 5 at 3 levels = 125 leaf runs from one delegation)
• [coordination][security] Supervision must not escalate authority — a delegation lends a goal, never privileges #185 — authority containment: a delegation lends a goal, never privileges (otherwise supervision is a consent bypass)

Sequence: #156 → #183 + #184 + #185 → #157 (result channel + escalation ladder) → #159 falls out → #160 (retire the workflow enum, the actual blocker on a configurable Coder).

Coder stays first consumer throughout: at each step its Overseer should be re-expressible in the primitive, and when it is, the hardcoded route comes out.