AI BriefingWorkflow SDK 5.3.1 introduces atomic idempotent starts to eliminate duplicate-run race conditions
·2026.11.04 09:00
Key point
The new atomic start() function admits a run and claims a hook in one step, using a domain-specific token as the idempotency key to ensure exactly one run owns the token.
Details
- Workflow SDK 5.3.1 replaces the previous getHookByToken() -then- start() pattern with an atomic start() function that admits a run and claims a hook in a single step, eliminating the documented duplicate-start race.
- The token serves as the idempotency key, derived from user domain data such as order, invoice, import, or request IDs; a duplicate start() throws HookConflictError carrying the owner's conflictingRunId and never creates a new run.
- The claimed Hook exists from the moment the run is admitted, allowing resumeHook to work before execution begins and buffering early payloads for in-order delivery.
- Setting experimental_minRetention keeps the token unavailable after the run ends, counted from start(), ensuring late duplicates are still refused.
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