The core objects
Everything in the API revolves around four objects:| Object | What it is | How it’s created |
|---|---|---|
| Definition | A reusable blueprint: steps, tasks, inputs, and flow-control logic | You create it via POST /definitions |
| Trigger | The act of running a definition with concrete input data | You call POST /definitions/{id}/trigger, or a scheduled job fires on a cron schedule |
| Job | One triggering event — it groups everything that trigger produced | Created automatically by every trigger |
| Execution | One durable run processing one set of inputs | Created automatically — one per job, or one per record when you trigger with a record array |
Request lifecycle
You trigger a definition
The API validates your request against the definition — the definition must be
active, and expressions and inputs are checked up front.A job and its executions are recorded
The trigger creates a job (status
pending, or scheduled if you passed scheduled_at) plus one execution per input set.Executions run durably
Each execution walks the definition’s steps in order. Tasks within a step run concurrently, and each task’s execution model controls when it fires — immediately, on a schedule, inside a time window, or on an external signal.
Results are tracked per execution
Task outputs feed later steps through expressions. When everything finishes, each execution records its
result or error, and the job aggregates them into a final status.Durable execution
Executions run on a durable-execution engine: a run’s progress is persisted at every step — a task can sleep for hours inside a business-hours window or wait a day for a webhook signal without holding anything open, and infrastructure interruptions don’t lose your work — the run resumes exactly where it left off. This is what makes long-lived patterns like scheduled, windowed, and signaled tasks safe to build on.Flow definitions
The anatomy of a definition: inputs, variables, steps, and tasks.
Jobs and executions
Status lifecycles, fan-out over records, and recurring triggers.
Execution models
Immediate, scheduled, windowed, and signaled tasks.
Build your first flow
Create, activate, and trigger a definition end to end.