| name | agent-composition-and-extensions |
| description | Use this skill when explaining how tools, skills, subagents, and capabilities change what an agent can do. |
Agent Composition and Extensions
Use this skill for questions about how an agent becomes more capable over time.
The four main extension layers
- Instructions shape the agent's default voice, boundaries, and purpose.
- Skills add on-demand manuals and deeper product or domain knowledge.
- Tools let the agent take structured actions or inspect structured data.
- Capabilities extend agent behavior at the product level, often changing how conversations or supporting workflows behave.
Subagents
- Subagents are specialist helpers the parent agent can delegate to when a focused task deserves its own expert behavior.
- They are useful when one agent needs a narrower workflow, such as mission authoring or other dedicated assistance.
Practical guidance
- Add a skill when the agent needs better guidance or explanations.
- Add a tool when the agent needs to act on structured inputs or external systems.
- Add a capability when the product experience itself needs to change around the conversation.
- Adjust the agent's model configuration when the behavior change is really about model choice or routing, including fallback resiliency, canary rollout, or A/B comparison.
- Use subagents for specialist workflows, not for routine product explanations.