Add OAuth state parameter to authorization URL#216
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Some production MCP servers (e.g. Ubersuggest / Neil Patel) reject authorization requests without a `state` parameter with `missing_state`, because RFC 6749 §4.1.1 lets the authorization server require it. @modelcontextprotocol/sdk does not include `state` when building the URL, so `mcpc login` against those servers failed before reaching the consent screen. Inject a random `state` in the `redirectToAuthorization` override when the SDK didn't supply one. PKCE already provides CSRF protection on this flow, so the value does not need to be persisted or verified — its sole purpose is server compatibility. Fixes #214
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Fixes #214
Summary
This change ensures that the OAuth authorization URL includes a
stateparameter when the SDK doesn't provide one. This fixes compatibility with authorization servers that require thestateparameter, such as Ubersuggest.Key Changes
randomBytesfrom thecryptomoduleredirectToAuthorizationoverride inperformOAuthFlowto inject a random 16-byte hex-encodedstateparameter if one is not already present in the authorization URLImplementation Details
stateparameter is generated usingrandomBytes(16).toString('hex'), providing a cryptographically secure random valuestateparameter, avoiding conflicts with SDK-provided valuesstateparameter per RFC 6749 §4.1.1, even though OAuth 2.1 treats it as RECOMMENDEDhttps://claude.ai/code/session_01DvJvUuWwHBT4VWoUZoqFhL