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How do I publish my MCP server to the official MCP registry?

Step by step to publish your MCP server to registry.modelcontextprotocol.io with mcp-publisher, what goes in server.json and how you prove the name is yours with GitHub or your domain.

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With the official mcp-publisher tool: you describe your server in a server.json file, prove the name is yours (with your GitHub account or with your domain, through DNS or a file on your site) and run mcp-publisher publish. The registry, at registry.modelcontextprotocol.io, stores only your server's listing (name, description, version and where to find it), and your code stays where it already lives.

Updated: November 2026

The registry opened in preview on September 8, 2025, according to the MCP project announcement, and its documentation still warns that it may ship breaking changes or reset data before general availability. Your listing's description can be up to 100 characters, according to the official server.json schema.

What is the official registry for?

It is the public catalog of MCP servers maintained by the MCP project itself, with an API to query it. The idea is for it to be the source other directories build on, including the server catalogs of some AI clients, which take that data and add their own. If your server is there, an agent or a directory looking for servers can find it without going through your site. What an MCP server is and how it differs from an API is in this guide, and the other places agents look for you are in how do AI agents find my API.

What name do I use and how do I prove it is mine?

The name depends on how you prove you own it:

How you prove itName formatWhat you need
With GitHubio.github.your-username/serverYour GitHub account and mcp-publisher login github
With DNScom.yourdomain/serverA TXT record on your domain and mcp-publisher login dns
With HTTPcom.yourdomain/serverA file at https://yourdomain.com/.well-known/mcp-registry-auth and mcp-publisher login http

In both domain options the name is reversed: example.com becomes com.example. For a business, a domain-based name looks more like your brand than your GitHub username does.

If you also distribute your server as a package, the registry checks that the package carries the same name: on npm, with the mcpName field in your package.json; on PyPI, with an mcp-name: <name> line in the README; on Docker, with the io.modelcontextprotocol.server.name label. If your server runs online and nobody installs it, you need no package at all.

What goes in server.json?

Three fields are required: name, description and version. For a server that is already online, you add remotes with the connection type and the URL, which has to answer publicly. A trimmed example:

{
  "$schema": "https://static.modelcontextprotocol.io/schemas/2025-12-11/server.schema.json",
  "name": "com.example/store",
  "title": "Example Store",
  "description": "Look up products, prices and availability at Example Store",
  "version": "1.0.0",
  "websiteUrl": "https://example.com",
  "remotes": [{ "type": "streamable-http", "url": "https://example.com/mcp" }]
}

Use streamable-http, since the sse transport is deprecated. The version has to be different on every publish, and what you publish under a version can no longer be changed: to fix the description, you publish 1.0.1.

What are the steps?

  1. Have your server online at a public URL, for example https://example.com/mcp.

  2. Install the tool with brew install mcp-publisher, or download the binary from the registry repository releases.

  3. Create your listing with mcp-publisher init in your project folder and edit the server.json it generates.

  4. Create your key and publish the public part. With the HTTP option:

    openssl genpkey -algorithm Ed25519 -out key.pem
PUBLIC_KEY="$(openssl pkey -in key.pem -pubout -outform DER | tail -c 32 | base64)"
echo "v=MCPv1; k=ed25519; p=${PUBLIC_KEY}" > mcp-registry-auth

    Upload that file to /.well-known/mcp-registry-auth on your domain. With DNS, the same line goes in a TXT record on your domain. The key.pem file is your private key, so keep it out of your repository.

  5. Log in with your key:

    PRIVATE_KEY="$(openssl pkey -in key.pem -noout -text | grep -A3 "priv:" | tail -n +2 | tr -d ' :\n')"
mcp-publisher login http --domain example.com --private-key "${PRIVATE_KEY}"

  6. Publish with mcp-publisher publish.

  7. Check it is listed with curl "https://registry.modelcontextprotocol.io/v0.1/servers?search=com.example/store".

If you would rather publish each version from GitHub Actions, the documentation has a ready workflow that logs in with mcp-publisher login github-oidc, with no stored secrets, when the name is io.github.*.

Does Peaje publish me to the registry?

No, you or whoever runs your website do that once, because proving the name is yours takes a key only you hold. What Peaje's free kit does is leave your MCP server answering on your domain, at /mcp, and publish the files that describe it at /.well-known/mcp and /.well-known/mcp/server-card.json, so an agent that reaches your site finds it (how to install it). With the kit installed, you put https://yourdomain.com/mcp as the URL in your server.json. The kit does not serve the mcp-registry-auth file, so upload it to your site yourself or use the DNS option.

Peaje followed these same steps: it is listed as com.usepeaje/peaje since October 29, 2026, proven over HTTP. The free radar checks, among other things, whether your MCP server shows up in a directory, so after publishing you can measure your site again.

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