Action Blocks

An action block is a reusable, parameterized sequence of steps an agent can invoke by name.

Use action blocks for deterministic procedures. If the sequence needs open-ended reasoning, use a skill or subagent instead.

In This Section

• Block schema
• Authoring locally
• Publishing

When action blocks are the right shape

• Procedural work with a fixed shape and varying parameters.
• Team-standardized operations that should execute identically.
• Compliance-bearing sequences where the order matters.
• Common operational routines currently living in shell scripts or CI jobs.

Consuming from an agent

async run(ctx, input) {
  return ctx.blocks.run("deploy-to-staging", { branch: input.branch });
}

Action block vs. skill vs. flow

Concern	Action Block	Skill	Flow
Branching	Static conditions	Arbitrary logic	Arbitrary
LLM involvement	None by default	Maybe	Often
Scope	Inside one agent run	Inside one agent run	Top-level orchestration

If the sequence is deterministic, use an action block. If it needs reasoning, use a skill. If it is orchestration across multiple agents or nodes, use a flow.

See also

• Skills
• Subagents
• Multi-Agent Orchestration