@corbits/credential-mcp

Important

This package moved to @corbits/credential-http, which also covers x-api-key, raw authorization and custom headers. New code should use it. The plugin key, the Bearer shape and the sentinel value are unchanged, so stored credential rows need no migration. The built-in Canva origin allowance is gone: pass it as extraOrigins.

@corbits/credential-mcp	@corbits/credential-http
createMcpStreamableHttpCredentialProvider(opts?)	unchanged, plus extraOrigins?
McpStreamableHttpCredentialProviderOptions	CredentialPresetOptions
MCP_STREAMABLE_HTTP_PROVIDER_KEY, MCP_NO_TOKEN_SENTINEL	unchanged
mcpOriginPinnedFetch({ pinnedOrigin, readToken, fetch? })	createOriginPinnedFetch({ origin, header: "authorization", readValue, extraOrigins?, fetch? }), where readValue returns Bearer <token> or undefined
McpOriginPinnedFetchArgs	OriginPinnedFetchOptions
resolveMcpTargetUrl, assertMcpPinnedTarget	removed; createOriginPinnedFetch does both
FetchLike	import from @intx/harness
Built-in https://mcp.canva.com → https://canva.ai allowance	extraOrigins: { "https://mcp.canva.com": ["https://canva.ai"] } on the provider, or extraOrigins: ["https://canva.ai"] on createOriginPinnedFetch

An MCP streamable-HTTP CredentialProvider for Interchange: a tenant-connected MCP server authenticates with authorization: Bearer <token> when the person supplied a token, and with no authorization header at all when they connected keyless. @intx/harness's vendored http provider can't express the keyless case — it always injects the stored secret — so a keyless connection stores MCP_NO_TOKEN_SENTINEL and this provider omits the header when it reads that sentinel back.

This package is a library only for now: registering a provider into the Interchange sidecar's CredentialProviderRegistry is blocked on an upstream hook, so a host wires it in by hand until that lands.

Install

bun add @corbits/credential-mcp

Usage

import {
  builtinCredentialProviders,
  createCredentialProviderRegistry,
} from "@intx/harness";
import { createMcpStreamableHttpCredentialProvider } from "@corbits/credential-mcp";

const providers = createCredentialProviderRegistry([
  ...builtinCredentialProviders(),
  createMcpStreamableHttpCredentialProvider(),
]);

A keyless MCP-server connection stores MCP_NO_TOKEN_SENTINEL as its credential's secret; this provider recognizes that value and sends no authorization header at all.

API

• createMcpStreamableHttpCredentialProvider(opts?) — the mcp-streamable-http provider (key MCP_STREAMABLE_HTTP_PROVIDER_KEY).
• MCP_NO_TOKEN_SENTINEL — stored-secret sentinel for a keyless connection.
• mcpOriginPinnedFetch, assertMcpPinnedTarget, resolveMcpTargetUrl — the shared origin-pinning building blocks (also used by an MCP connect-time probe), including an explicit extra-origin allowlist for MCP servers whose protocol origin differs from their stored base URL (e.g. Canva's https://mcp.canva.com → https://canva.ai).

Every request is pinned to the credential's origin (plus any allowlisted extra origin) and forces redirect: "manual" so a 3xx never sends a token to a foreign host.

License

LGPL-2.1-only.