Skip to content
openapi-mcp

Moving your MCP server off Stainless

Stainless is winding down hosted products. Step-by-step guide to regenerating your MCP server from OpenAPI with openapi-mcp-generator and deploying to Cloudflare.

By Updated

Regenerate an MCP server from the same OpenAPI spec with the open-source openapi-mcp-generator, then run it yourself on Cloudflare Workers.

What was announced#

  • Stainless announced on 18 May 2026 that it is joining Anthropic.
  • Stainless has closed new signups.
  • Stainless is winding down its hosted products.

Read the Stainless announcement

For timelines and anything specific to your account, rely on Stainless's own communication. This guide is not affiliated with Stainless or Anthropic.

Migration steps#

1. Locate your OpenAPI spec#

Find the OpenAPI 3.x document that describes your API, in JSON or YAML. It might live in your repository or be published with your API docs. A local file path or a public URL both work.

2. Generate the MCP server#

You'll need Node.js 22.19 or later.

bash
npx openapi-mcp-generator@5 --input ./openapi.json --output ./my-mcp --transport=cloudflare-worker --inbound-auth bearer

Large API? Expose only the operations an agent needs. See Large APIs.

3. Choose a transport#

Transport Use it when
cloudflare-worker You want a hosted URL on your own Cloudflare account
streamable-http You run a Node.js server and clients connect over HTTP
web A client needs the older SSE transport
stdio The client launches the server locally (desktop apps, CLIs)

More detail in Transports.

4. Deploy to Cloudflare Workers#

bash
cd my-mcp
npm install
npx wrangler deploy

Full walkthrough, secrets and auth options: Deploy to Cloudflare Workers.

5. Or join the MCP Cloud beta#

Prefer not to run it yourself? MCP Cloud is a hosted option in Private beta.

It isn't live yet. Join the waitlist and we'll be in touch when a spot opens.

Join the Cloud beta

All guides