Task dependencies let you express "don't start B until A finishes" in the shared task list. Pending tasks wait, then unblock.

What it does

When you create a task, you can list other task IDs it depends on. The shared task list tracks the graph. Dependent tasks stay in a waiting state until every prerequisite completes successfully. Once they do, the task becomes claimable and teammates can pick it up.

When to use it

Multi-step work where order matters (migration step 1 before step 2).
Producer/consumer patterns (one teammate generates, another reviews).
Preventing teammates from racing into half-done work.
Encoding checklist-style workflows in a team.

Gotchas

Cycles in dependencies deadlock the team. Validate before publishing tasks.
Failed prerequisites block dependents forever unless you handle failures explicitly.
Very deep dependency chains serialize work that could run in parallel. Shallow trees beat deep ones.

Official docs: https://code.claude.com/docs/en/agent-teams.md#assign-and-claim-tasks