Coordinate Agents

Coordinating work across coding agents

You are the coordinator: you own the task definition, review every deliverable, and decide what happens next. Every other agent is a worker: it receives a spec, produces an artifact, and stops. There is no cross-vendor message bus, so coordination is turn-based and file-mediated:

you write task.md -> worker runs headlessly -> worker writes result.md ->
you read, verify, decide the next turn

If agent-sync is installed, run agent sync before delegating so every worker starts with the same synthesized memory you have.

1. Write the task directory

task/
  task.md      # the spec (see contract below)
  ...inputs... # everything the worker needs; workers get no other context
  result.md    # the worker writes this; its existence signals completion

task.md is a contractor brief and must contain:

• the goal, in one paragraph;
• the exact deliverable (a file, named);
• a checkable definition of done;
• the instruction to stop after writing the deliverable;
• the lock or worktree rules from section 2 when the worker will edit a shared tree.

2. Choose the sharing mode BEFORE invoking anyone

Rule zero: two agents must never mutate the same working tree at the same time.

Same-dir lock (mkdir is atomic; put these instructions in task.md too):

until mkdir .agent-lock 2>/dev/null; do sleep 1; done   # acquire
echo "$(whoami):$$" > .agent-lock/owner
# ... work ...
rm -rf .agent-lock                                       # release

Never auto-expire a lock by age: a slow worker looks identical to a dead one. Verify the worker process is dead before clearing a stale lock.

Worktree mode: git worktree add ../task-<worker> -b agent/<worker> per worker, workers never push and never touch each other's trees, the main checkout stays read-only, and you (the coordinator) do all merging as the one serialized step.

3. Invoke the worker headlessly

Rules that were learned the hard way:

• Run the worker from inside the task directory and scope its write access to it.
• Close stdin (</dev/null) for any backgrounded worker or it may hang waiting for input.
• Codex refuses untrusted non-git directories without --skip-git-repo-check.

4. Verify, then decide

• The worker's word is not the deliverable. Read result.md and check it against the definition of done; for code, run the tests yourself.
• A missing or wrong deliverable gets a new turn with a sharper spec, not a retry of the same one.
• You stay responsible for everything you accept: review a worker's diff as you would a human contractor's PR.

Boundaries

• Never give a worker credentials, deploy rights, or access to real audiences; workers produce artifacts, the coordinator (with the user) ships them.
• Never run this protocol to parallelize edits inside one tree without locks or worktrees, even for "quick" tasks.
• The user decides which agent plays coordinator; do not hand off coordination to a worker.