MCP server

Pewter runs a Model Context Protocol server so assistants and agents can browse capacity, manage listings, pair machines and run jobs with the same rules as the REST API.

• Endpoint: https://api.example/api/v1/mcp (HTTP). Client-specific profiles live at /api/v1/mcp/claude and /api/v1/mcp/chatgpt.
• One server, filtered per caller. An omk_ agent key sees every tool. A sign-in token sees only the tools its scopes allow, further capped by the profile it was issued for.
• No tool moves money. Payments, wallet and account management are app-only.

Signing in from an assistant (OAuth)

Assistants that support MCP sign-in discover Pewter through standard OAuth metadata at /.well-known/oauth-authorization-server, then send you to a Pewter page to approve or decline.

• Approved clients only. A client's redirect address must be on Pewter's allowlist: Claude, ChatGPT, Cursor and VS Code callbacks, plus approved loopback callbacks for local tools. Anything else is refused.
• Client ID metadata documents. A client may identify itself with an HTTPS URL that serves its metadata. Pewter fetches it with strict guards: HTTPS on the default port only, a host name (not an IP), no private or loopback destinations, no redirects, a 5-second timeout and an 8 KB cap. The host is resolved twice and the connection is pinned to the address that was checked, so a DNS-rebinding answer is refused.
• Grants can be listed and revoked (/api/v1/oauth/grants).