Unified Access Gateway

A unified access gateway aggregates the tools from multiple upstream MCP servers behind a single MCP endpoint. Instead of advertising a separate connection for every MCP server, you hand your users one endpoint: they authenticate once through your identity provider, authorize the upstreams they need, and receive one tool list with every tool namespaced by its upstream (for example, github__create_issue). You control which upstreams the gateway exposes and who can access them via Access Policies.

Before starting:

• A Keycard Zone with a connected identity provider
• One or more upstream MCP servers configured in your Zone, for example installed from the Catalog
• Manager access to the Zone (see Roles & Permissions)

1. Create a gateway Application

   In Keycard Console, click Applications in the sidebar and click Create application. In the form, enable the Proxy MCP Tools toggle to aggregate all tools from MCP servers through a single URL.

   Field	Value
   Name	<gateway-name>
   Proxy MCP Tools	Enabled
   Documentation URL	Optional
   Description	Optional

   Enabling Proxy MCP Tools removes the identifier, consent, and redirect URL fields from the form: the gateway’s MCP URL is generated for you when the Application is created.

2. Attach upstream MCP servers

   On the gateway’s detail page, under Dependencies, click Add dependency and select each upstream MCP server to expose through the gateway, for example Linear and GitHub.

   Only Resources already configured in the Zone appear in the list. To add a new upstream, install a third-party MCP server from the Catalog, or configure an internal MCP server on the Console -> Resources page first.

3. Grant access (optional)

   By default, the Zone’s managed Policies permit all authenticated users to access the gateway and its upstreams. To restrict access, add a Policy that permits only specific users or groups.

   Click Policies in the sidebar and create a Policy scoped to the gateway’s Resource identifier, which follows the format https://<gateway-name>.<zone-id>.mcp.gateway.context/mcp. For example, permit only members of the Law Study Group IdP group:

   @id("permit-law-study-group-gateway")
   permit (
     principal is Keycard::User,
     action,
     resource
   ) when {
     resource.identifier == "https://<gateway-name>.<zone-id>.mcp.gateway.context/mcp" &&
     context has subject_claims &&
     context.subject_claims has groups &&
     context.subject_claims.groups.contains("Law Study Group")
   };

   See Access Policies for authoring and activating Policies.

4. Share the endpoint with your users

   Open the gateway’s Application settings page and copy the MCP Access URL using the copy button next to the field. Distribute this URL to your users: each user adds this single URL to their MCP client, signs in through the identity provider, and authorizes the upstreams they need.

   Optionally, users can use the Keycard CLI to automatically discover the endpoint and configure it in a supported coding agent for them.

Add the gateway endpoint to an MCP client, sign in as a user with access (for example, annie.edison@greendale.edu), and authorize the upstreams when prompted. In Claude Code, run /mcp and confirm the gateway appears with an aggregated tool list where every tool carries an upstream prefix, such as github__create_issue and linear__list_issues.

To confirm tool calls flow through the gateway, invoke a tool and check Console -> Audit Log for the event showing who invoked which tool on which upstream.

• A user doesn’t see tools from an upstream. The user is either not permitted by Policy or has not authorized that upstream. Check your access Policies for the upstream Resource, then have the user reconnect and complete the authorization prompt.
• A newly attached upstream doesn’t appear for existing users. Users who signed in before the upstream was attached must sign in again to issue grants for it. Have them log out of the gateway connection and reconnect.
• A user lost access to an upstream mid-session. If the upstream does not support refreshable grants, the user must sign in again to restore access.

• Restrict who can reach each upstream with Access Policies.
• Gate individual tool calls with Fine-Grain Authorization.
• Add more upstream MCP servers from the Catalog.
• Review tool call events in the audit log, or export them with Audit Log Export.