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Subagent

A subagent is a specialized assistant I hand a specific slice of the work to.

Agent 4 min read Updated 2026-05-22
— Definition

Subagent, in plain words

A subagent is a specialized assistant I hand a specific slice of the work to.

Present the subagent as a specialist you call at the right moment, not a universal clone.

A concrete example

My main agent writes the article. For the research, it delegates to an Explore subagent. For the review, to a Code Review subagent.

Why it matters

A subagent keeps a clean context and a sharp specialty. You stop your main agent from mixing everything together.

You run into it in Codex, Claude Code, research workflows, reviews, and multi-agent curation.

Don't mix it up with

Agentic workflow: An agentic workflow is a sequence of steps where the AI plans, uses tools, checks its work, and keeps going until it hits the result.

Multi-agent: A multi-agent system puts several specialized agents to work on the same mission.

Common mistakes

  • Spinning up a subagent for every little thing and losing the benefit.
  • Forgetting to define the subagent's mission clearly.
  • Not passing it the right info as input.

Quick checklist

  • First I check whether the word names a concept, a tool, a risk, or a metric.
  • I tie it to a concrete case: My main agent writes the article. For the research, it delegates to an Explore subagent. For the review, to a Code Review subagent.
  • I keep the main trap in mind: Spinning up a subagent for every little thing and losing the benefit.

Quick questions

What is Subagent in AI?

A subagent is a specialized assistant I hand a specific slice of the work to.

Where will I run into Subagent?

You run into it in Codex, Claude Code, research workflows, reviews, and multi-agent curation.

Which word should I read next?

Start with Agentic workflow, Multi-agent, Skill & Agent.

Want to keep going in order?

Head back to the full glossary, search a word, then open only the pages that deserve more than a short definition.

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