Assign roles, contracts and acceptance criteria

One task, one owner, one write set. If two workers edit the same deliverable, you have two tasks or a missing interface task. Anything outside the write set is out of scope. If a worker thinks it needs another file, it stops and writes the request in its handoff. You either expand the contract or add a task. Silent extra edits are the failure this rule exists to prevent.

For the default due/tags/search plan, each feature worker owns src/features/<name>.ts and src/features/<name>.test.ts. src/types.ts and src/store.ts stay with the interface task. src/main.ts is not secretly owned by everyone: it is the documented merge point. Do not tell a worker “never edit src/main.ts” unless the interface task already extracted a registry file those workers import. This starter’s registration list lives in src/main.ts; Lesson 5 needs that real conflict.

The starter's complete opencode.json declares Agent-DUE, Agent-TAGS, and Agent-SEARCH with a 20-step cap. Each can edit only its own feature implementation and HANDOFF.md; its test and the shared registration list require approval. Shared types, storage, config, and another worker's files are denied. Read the file, then confirm the exact names:

opencode debug config
opencode agent list

These roles use mode: "all" because later lessons start them directly with --agent; that mode also permits use as a subagent. A role with mode: "subagent" is for delegation or @mention, not this direct-session recipe. The configuration contains no model id or key; it uses your existing supported provider connection from /connect. An eligible LintLabs key uses OpenRouter; other supported providers use their own authentication flow. Free lessons do not include API credits. Check costs and spending limits before starting multiple agents. These agent-run exercises require a working connection; reading the instructions alone is not evidence that agents ran.

Pattern order matters: "*": "deny" comes first, then narrow overrides. These are tool gates, not a sandbox. Read any approval request. Do not use --auto. The learner reviews and commits each worker's result.

A contract is the frozen interface between tasks. Write it in the task brief before the worker starts. Name types and fields (Task.due?: string as ISO YYYY-MM-DD), exports (isOverdue(task, today): boolean), DOM hooks (data-feature="due"), and a registration rule for src/main.ts (add your Feature; do not delete another worker’s import). Include a do not touch list: other feature files, tests you do not own, dependency files, and CI config.

If a worker wants a different signature, that is a contract change. You decide, re-run the interface task, then continue. Workers do not invent a second Task shape. Keep the brief short enough to paste; dump the whole orchestration plan into every prompt and the contract disappears under noise.

Copy TASK.md.example to TASK.md in the due worktree. It contains a complete due-date brief and observable checks. For tags/search, make a separate adapted brief with that worker's name, files, contract, port, and checks. HANDOFF.md.example is the output template. These files are ordinary documents, not hidden OpenCode APIs.

Each criterion is binary, observable, and checkable by someone who did not write the code. Use Given … when … then …, checked by …. Include one edge and one regression (add / complete / remove still work; npm test and npm run typecheck still pass).

Example for due dates: a task due yesterday, not done, shows an Overdue badge (browser); due today shows none; done + past due shows none (unit test); missing due renders nothing date-related; baseline CRUD still works. “The agent said it is done” is not a criterion. You will re-run these checks yourself in Lesson 4. Least privilege is only real if you try to break it: ask the due worker to edit src/features/tags.ts and record the deny.