Mastra

# Mastra Framework Guide

Build AI applications with Mastra. This skill teaches you how to find current documentation and build agents and workflows.

## Critical: Do not trust internal knowledge

Everything you know about Mastra is likely outdated or wrong. Never rely on memory. Always verify against current documentation.

Your training data contains obsolete APIs, deprecated patterns, and incorrect usage. Mastra evolves rapidly - APIs change between versions, constructor signatures shift, and patterns get refactored.

## Prerequisites

Before writing any Mastra code, check if packages are installed:

```bash ls node_modules/@mastra/ ```

- If packages exist: Use embedded docs first (most reliable) - If no packages: Install first or use remote docs

## Resources

### References

| User Question | First Check | How To | | ----------------------------------- | ---------------------------------------------------------------- | ---------------------------------------------- | | Create/install Mastra project | [`references/create-mastra.md`](references/create-mastra.md) | Setup guide with CLI and manual steps | | Choose Agent/Workflow/Tool/Memory/Storage | [`references/core-concepts.md`](references/core-concepts.md) | Core concepts and when to use each primitive | | How do I use Agent/Workflow/Tool? | [`references/embedded-docs.md`](references/embedded-docs.md) | Look up in `node_modules/@mastra/*/dist/docs/` | | How do I use X? (no packages) | [`references/remote-docs.md`](references/remote-docs.md) | Fetch from `https://mastra.ai/llms.txt` | | Choose or validate a model | [`references/model-selection.md`](references/model-selection.md) | Model format and provider registry lookup | | I'm getting an error... | [`references/common-errors.md`](references/common-errors.md) | Common errors and solutions | | Upgrade from v0.x to v1.x | [`references/migration-guide.md`](references/migration-guide.md) | Version upgrade workflows | | Inspect/call server resources via CLI | [`references/mastra-api.md`](references/mastra-api.md) | `mastra api` CLI for local, Mastra platform, or remote servers | | Find exact traces with complex predicates | [`references/trace-query.md`](references/trace-query.md) | Query completed traces by trace fields or related spans, scores, and feedback | | Investigate agent health, recurring failures, or improvement opportunities | [`references/trace-intelligence.md`](references/trace-intelligence.md) | Start with aggregate Trace Intelligence themes, then inspect trace/log evidence |

### Scripts

- `scripts/provider-registry.mjs`: Look up current providers and models available in the model router. Always run this before using a model to verify provider keys and model names.

## Priority order for writing code

Never write code without checking current docs first.

1. Embedded docs first (if packages installed)

Look up current docs in `node_modules` for a package. This matches the exact installed version and is the most reliable source of truth. See [`references/embedded-docs.md`](references/embedded-docs.md).

2. Source code second (if packages installed)

If embedded docs don't cover the question, inspect the installed source and type definitions. This is the source of truth when docs are missing or unclear. See [`references/embedded-docs.md`](references/embedded-docs.md).

3. Remote docs third (if packages not installed)

Use the latest published docs when packages are not installed or when exploring new features. Remote docs may be ahead of the user's installed version. See [`references/remote-docs.md`](references/remote-docs.md).

## Core concepts

Use [`references/core-concepts.md`](references/core-concepts.md) when choosing between agents, workflows, tools, memory, and storage.

- Agent: Use for open-ended tasks that make decisions and use tools. - Workflow: Use for defined multi-step processes.

## Mastra Studio

Studio is the interactive UI for building, testing, and managing agents, workflows, and tools. Use Studio when advising a human to inspect or debug visually.

Inside a Mastra project, run:

```bash npm run dev ```

Then open `http://localhost:4111` in a browser to show Mastra Studio to your human user.

## Mastra API CLI

Use `mastra api` to inspect or call resources on local dev servers, Mastra platform deployments, or remote Mastra endpoints. It is useful for agent-readable state, execution, traces, logs, scores, threads, and workflow operations. See [`references/mastra-api.md`](references/mastra-api.md) for usage patterns.

For exact trace selection that needs recursive predicates or conditions over related spans, scores, or feedback, read [`references/trace-query.md`](references/trace-query.md). Before using `mastra api trace query`, co