Mastra

Documentation lookup guide

Quick Reference

Priority order for writing code

⚠️ Never write code without checking current docs first

1. Embedded docs first (if packages installed)

   # Check what's available
   cat node_modules/@mastra/core/dist/docs/SOURCE_MAP.json | grep '"Agent"'
   
   # Read the actual type definition
   cat node_modules/@mastra/core/dist/[path-from-source-map]
   

   • Why: Matches your EXACT installed version
   • Most reliable source of truth
   • See: references/embedded-docs.md

2. Remote docs second (if packages not installed)

   # Fetch latest docs
   # https://mastra.ai/llms.txt
   

   • Why: Latest published docs (may be ahead of installed version)
   • Use when: Packages not installed or exploring new features
   • See: references/remote-docs.md

Core concepts

Agents vs workflows

Agent: Autonomous, makes decisions, uses tools Use for: Open-ended tasks (support, research, analysis)

Workflow: Structured sequence of steps Use for: Defined processes (pipelines, approvals, ETL)

Key components

• Tools: Extend agent capabilities (APIs, databases, external services)
• Memory: Maintain context (message history, working memory, semantic recall)
• RAG: Query external knowledge (vector stores, graph relationships)
• Storage: Persist data (Postgres, LibSQL, MongoDB)

Critical requirements

TypeScript config

Mastra requires ES2022 modules. CommonJS will fail.

{
  "compilerOptions": {
    "target": "ES2022",
    "module": "ES2022",
    "moduleResolution": "bundler"
  }
}

Model format

Always use "provider/model-name":

• "openai/gpt-4o"
• "anthropic/claude-3-5-sonnet-20241022"
• "google/gemini-2.5-pro"

When you see errors

Type errors often mean your knowledge is outdated.

Common signs of outdated knowledge:

• Property X does not exist on type Y
• Cannot find module
• Type mismatch errors
• Constructor parameter errors

What to do:

1. Check references/common-errors.md
2. Verify current API in embedded docs
3. Don't assume the error is a user mistake - it might be your outdated knowledge

Development workflow

Always verify before writing code:

1. Check packages installed

   ls node_modules/@mastra/
   

2. Look up current API

   • If installed → Use embedded docs references/embedded-docs.md
   • If not → Use remote docs references/remote-docs.md

3. Write code based on current docs

4. Test in Studio

   npm run dev  # http://localhost:4111
   

Resources

• Setup: references/create-mastra.md
• Embedded docs lookup: references/embedded-docs.md - Start here if packages are installed
• Remote docs lookup: references/remote-docs.md
• Common errors: references/common-errors.md
• Migrations: references/migration-guide.md
• Official site: https://mastra.ai (verify against embedded docs first)