Deep Agents/Customization
Advanced10 min

Customizing Deep Agents

Custom tools, filesystem backends, planning strategies, middleware, subagent configuration, and deployment — everything you need to tailor Deep Agents for your production use case.

Quick Reference

  • →Add custom tools alongside built-in tools — your tools + planning + filesystem + subagents
  • →Implement custom filesystem backends (S3, database, etc.) via the BackendProtocol
  • →Override planning behavior by customizing the write_todos tool
  • →Integrate LangChain middleware for guardrails, PII filtering, and context engineering
  • →Deploy on Agent Server with assistants API for versioned, multi-tenant deployments
  • →Expose via ACP (IDE), MCP (tools), or A2A (agent-to-agent) protocols

Adding Custom Tools

Custom tools alongside built-in capabilities
Tool priority
Custom tools appear alongside built-in tools. The agent decides which to use based on tool descriptions. Write clear, specific descriptions so the agent picks the right tool — 'Query the analytics PostgreSQL database for metrics' is better than 'Run SQL'.