Dispatch Agent

Dispatch — claude arm

Spawn a worker via the Agent tool. The harness-identical funnel and drive loop live in the `/dispatch` router — this skill is only the spawn template.

Pre-spawn — arm the base, cd into the spawn dir

The worker's worktree is created by doctrine's WorktreeCreate hook (doctrine worktree create-fork), not natively by the harness. The hook discriminates a dispatch worker positionally: a spawn is a dispatch worker iff the Agent payload cwd is the arming dir <coord>/.doctrine/state/dispatch/spawn/. The base it forks is explicit — the base file in that dir — never cwd HEAD. cwd is the discriminator, not the base source.

Before every spawn (or parallel batch): 1. doctrine dispatch arm-spawn --base <B> [--slice <N>] — writes <coord>/.doctrine/state/dispatch/spawn/base = <B> and prints the spawn dir's absolute path. Idempotent: re-arming at B′ rewrites base. 2. cd into that spawn dir. This is the arming signal — the hook forks at B only when the payload cwd is the spawn dir. 3. Issue the Agent spawn(s) (below). File-disjoint parallel batch: arm once, then issue N spawns from the spawn dir — all read the same B; each hook derives its own branch/dir from its own name. 4. cd back to the coord root after the spawn(s) — positional disarm. A benign isolation:worktree spawn issued from the coord root passes through (provisioned, not worker-forked); only a spawn from inside the spawn dir is a dispatch worker. A lingering base file is inert — the trigger is cwd-position, not file-presence.

Serial drive: re-arm each phase — arm at B, cd in, spawn, cd back; the funnel commit advances coord HEAD; arm at B′ for the next phase. Base is explicit, so coord-HEAD drift between arm and create is irrelevant. Default cwd is the coord root; step into the spawn dir only to issue worker spawns.

Placement precondition (ISS-031): the coordination worktree (and so its arming dir) MUST live inside the project root — convention .dispatch/SL-<n> (dispatch setup --dir .dispatch/SL-<n>). Under a cwd-confining jail (bubblewrap rooted at /workspace/<repo>), a cd to an outside sibling silently reverts to the project root on the next Bash call. dispatch setup fails closed on the claude arm when --dir resolves outside the root. Confirm placement with a bare cd <spawn-dir> ; pwd in a separate Bash call before trusting it.

Spawn

BASE GUARD — run FIRST, before any read/edit/commit. STOP and write nothing if any check fails: 1. git status --porcelain → MUST be empty (clean tree) 2. git rev-parse --git-dir vs --git-common-dir → MUST differ (isolated linked worktree, not main tree) 3. git merge-base --is-ancestor <B> HEAD → MUST exit 0 (HEAD descends from base <B>) 4. grep prerequisite seams: <seams> → MUST be present On any failure: STOP, author/commit nothing, report "base-guard-failed: <check>".

Check #2 is the in-worker mirror of the orchestrator's not-isolated belt — if the worker's git-dir equals git-common-dir, it is not an isolated worktree.

subagent_type: dispatch-worker
isolation: worktree
prompt: <pre-distilled worker prompt, including the base-guard block above>

Post-spawn (pre-funnel gate, claude arm)

1. Read the Agent return footer for worktreePath:. NO footer / no worktreePath: ⇒ no isolated tree was created (hook abort or fallback-to-main) ⇒ ABORT, do NOT enter the funnel. Re-dispatch, or switch to the subprocess arm if the hook is failing. 2. Derive the worker's identity from worktreePath (the normative datum; P2/I3): name = basename(worktreePath), branch = dispatch/<name>. Do NOT read the footer's worktreeBranch field — it is undefined for the hook-created tree (PHASE-04 VA-1, live 2.1.181). 3. doctrine worktree verify-worker --base <B> --dir <worktreePath> --branch <derived branch> Abort on any refusal: no-worker-head / not-isolated / unstamped / wrong-base / branch-mismatch. (--branch binds dir↔branch — both belts then verify ONE worker state.) 4. Hand the derived <branch> to the funnel as S.

Boundary recording

After the batch's code commit and before the knowledge commit: doctrine dispatch record-boundary --slice <N> --phase PHASE-NN --code-start <B> --code-end <B+1>. Claude-arm-only (no fork branch); skip on codex/pi. One call double-writes both registries (dispatch.rs): the committed phase/<N> ref-cut and the primary-tree conformance registry (F-6 guard, upsert by phase). The committed ledger is also what dispatch sync --prepare-review re-derives the registry from (auto-heal) before the completeness gate runs — so on this arm registry capture is enforced machinery, not a step the orchestrator can forget. The claude arm therefore needs no funnel slice record-delta step; record-delta survives on this arm only as the manual escape hatch (correct a range / bootstrap a pre-binding phase).

Red Flags

Never: spawn without first arm-spawn-ing and cd'ing INTO the spawn dir (a spawn from the coord root is a benign pass-through, never a dispatch worker); read the footer's worktreeBranch (undefined for the hook-created tree — derive branch = dispatch/basename(worktreePath) instead); funnel a worker that returned no worktreePath: footer; point dispatch setup --dir at an outside-root sibling on the claude arm (the cd silently reverts under a jail; use .dispatch/SL-<n>); spawn with a subagent_type other than dispatch-worker; run fork or bwrap here (that's /dispatch-subprocess); claim parallel landing (v1 lands one per base). Always: arm-spawn --base B then cd into the spawn dir before the spawn, cd back to the coord root after; pin subagent_type to dispatch-worker; embed the base-guard block in the distilled worker prompt; derive branch from worktreePath; run verify-worker before import; return to the router for the funnel cadence.