Connect an agent over MCP

How the server works

Remote only

Streamable HTTP. There is no stdio deployment and no local package to install.

Protocol revision 2026-07-28

Stateless request and response, no initialize handshake, and the version negotiated per request.

OAuth 2.1

The server is a resource server: it verifies bearer tokens and never issues one. The authorization server is separate, and the console is the sign-in screen.

Read only

Every tool is annotated read_only_hint and closed world. Those are hints to the client, not a security boundary.

Connect

In Claude or ChatGPT, add a custom connector in Settings, paste the server address below, and sign in to Placestack when you are asked. The agent then calls as you: it sees what you can see, and its lookups count against your usage.

https://mcp.placestack.com/mcp

Authenticate

A client does the discovery and the token exchange itself. An unauthenticated request gets a 401 whose WWW-Authenticate header points at the protected resource metadata:

https://mcp.placestack.com/.well-known/oauth-protected-resource/mcp

That document names the authorization server, and the client takes it from there. Tokens are bound to this server: send the canonical resource URI as the RFC 8707 resource parameter, and the server checks the audience on every request. A token that is missing a scope gets a 403 with error="insufficient_scope" naming what it needs, which is what a client uses to ask you for more access rather than simply failing.

Signing keys are discovered from whatever the issuer publishes, authorization server metadata first and OpenID Connect discovery after, and discovery happens on the first token rather than at startup. Changing identity provider is a configuration change.

Tools

Two tools, and what each one returns, are on the next page.

The tool surface →