Quickstart
This guide gets you from zero to a verified SDK call. It also shows the two paths agents use most often: anonymous sandbox execution and MCP setup.
Requirements
- Node.js 18 or newer.
- An ESM project (
"type": "module"inpackage.json) for direct Node scripts. - A Recursiv API key for authenticated resources.
- No API key for the anonymous sandbox.
Install the SDK
Configure an API key
No account yet? Sign up at recursiv.io/register, then create a key at recursiv.io/account/api-keys (Settings → API Keys). You can also sign up and mint a key entirely programmatically — see Autonomous onboarding.
The SDK reads RECURSIV_API_KEY by default. You can also pass apiKey directly:
Create a project and make your first authenticated call
Most resources hang off a project. Create one first — project IDs are UUIDs (e.g. 019d45b3-fc34-76ee-a2dc-1f7131f5447e), so always use the id the API returns. Project-scoped calls return { data }.
Run code without signing up
The anonymous sandbox is useful for docs examples, demos, and first-run agent checks.
Limit: 10 anonymous executions per IP per day.
Stream from an agent
Use chatStream() in Node.js and browsers:
React Native does not expose ReadableStream consistently. Use chatStreamText() or follow the React Native guide.
Start a project sandbox
Use project sandboxes when the code needs project files, dependencies, deploy previews, or persistence.
Deploy
Deploys build from the project’s linked GitHub repository — a project without a repo_url fails with “Project has no linked repository”. No repo yet (or no GitHub account)? Scaffold one server-side from a Recursiv starter template:
Already have a repo? Pass its URL as repo_url on projects.create (or link it later with projects.update).
Use the CLI
deploy requires a target: vercel, docker, render, railway, or cloud.
Connect an MCP client
Use MCP when an AI coding assistant should call Recursiv tools directly.
For local development from this repo, build the MCP package first and point your client at packages/mcp/dist/bin.js.
Use REST
What’s next?
- Concepts - Understand how projects, agents, and organizations fit together
- SDK Reference - Full SDK documentation with all 40+ resources
- Build an AI-Native App - End-to-end tutorial: database + agent + auth + deploy
- Build an Autonomous Agent - Give an agent its own Postgres, memory, and code execution
- CLI - Scaffold, develop, and deploy from the terminal
- MCP - Give an AI assistant native access to Recursiv via tool use
- API Reference - Full REST API documentation