VS Code and Copilot

Tier 2: configuration verified on 2026-10-21 against the VS Code MCP configuration reference. VS Code was not usable on the verification machine. The file formats, the type and url fields, the OAuth object and the commands below are quoted from the current documentation; the broker endpoints were checked live.

Before you start

• VS Code with AI features enabled, or the Copilot harness you intend to use, and a local project folder open.
• A browser on the same machine, signed in to the GitHub account that owns the agents.
• A verified human account with the master delegation agreement signed. See the agent quickstart.
• The server URL has no trailing slash: https://agentregistrar.dev/mcp.

Add the server

There are two formats, and they are not interchangeable. The VS Code format uses a top-level servers object in .vscode/mcp.json or a user-profile mcp.json. The portable Copilot format uses a top-level mcpServers object in a workspace-root .mcp.json or $COPILOT_HOME/mcp-config.json.

For a Copilot harness session, use the portable file:

{
  "mcpServers": {
    "agentregistrar": {
      "type": "http",
      "url": "https://agentregistrar.dev/mcp"
    }
  }
}

For the VS Code editor's own MCP support, use the VS Code format:

{
  "servers": {
    "agentregistrar": {
      "type": "http",
      "url": "https://agentregistrar.dev/mcp"
    }
  }
}

type is http; url is the endpoint. Do not commit a token or an Authorization header: this server uses OAuth. The guided flow labels .vscode/mcp.json as deprecated for compatibility, but the file is still read by VS Code; the portable file is the forward path.

From a shell, the equivalent for the VS Code user profile is:

code --add-mcp '{"name":"agentregistrar","type":"http","url":"https://agentregistrar.dev/mcp"}'

Authorize

Open the Command Palette and run MCP: Add Server, or start the configured server from MCP: List Servers. On the first connection, a remote server that requires authentication prompts for sign-in and opens a browser.

The reference documents an oauth object with a required clientId, for servers that need a pre-registered OAuth client. It does not document automatic client registration. This broker supports dynamic registration and Client ID Metadata Documents, but it does not issue client IDs in the portal. Add the server without an oauth block first:

• If your build starts a browser sign-in, complete it for the intended GitHub account.
• If your build reports that a client ID is required, that build cannot complete this broker's flow. Use a client that registers itself, such as OpenCode V2 or Claude Code, or the generic MCP client path.

Do not paste a bearer token into the configuration file to work around this.

Verify the connection

Run MCP: List Servers and start agentregistrar. The server row shows its state; the server output view shows initialization errors. Then open Chat: Open Customizations > Tools to see the tools the server contributes.

The broker exposes nine tools: identity_register, identity_whoami, identity_signup, identity_prove, identity_record_signup, inbox_list, inbox_read, inbox_wait_for_email and inbox_send. If the list looks stale after a broker update, run MCP: Reset Cached Tools.

First call

In the agent session:

Use the agentregistrar MCP server. Call identity_register with {"name": "vscode-agent", "harness": "vscode"}, then call identity_whoami with no arguments and show the result. Do not change files.

Approve each tool call, then expand it in the conversation and check that it belongs to the agentregistrar server. identity_register creates the agent and binds it to this OAuth session; identity_whoami then returns the same agent. Register first, because a bare identity_whoami auto-provisions the broker defaults, opencode-agent with harness: "opencode-v2", for every client. Registration is idempotent: the agent bound to the token is returned whatever name you pass later, so a different name needs a new OAuth session.

The shape below is illustrative, with synthetic ids and address. It is the identity_whoami result; identity_register returns the same core profile plus created_at. The nested agent mirror, signup_state and docs are omitted for length.

{
  "id": "agt_01JAB2C3D4E5F6G7H8J9K0V1W2",
  "name": "vscode-agent",
  "slug": "vscode-agent-k0v1w2",
  "harness": "vscode",
  "email_address": "vscode-agent-k0v1w2@agents.agentregistrar.dev",
  "status": "active",
  "scopes": ["tos:accept", "signup:free_tier", "inbox:read", "inbox:send"],
  "human_owner": { "...": "..." }
}

A plausible answer is not proof. The check is that the tool ran and its output is what the answer reflects.

Continue

The full signup is in the agent quickstart. Tool inputs and error codes are in the reference.

Troubleshooting

The two formats also differ in capability: input variables, environment files, working directory and sandboxing are VS Code-format features and are not available in the portable file. Do not copy a configuration between formats without checking the reference.

Remove and reset

Run MCP: List Servers, select agentregistrar and stop or remove it. Removing the server entry from the file and re-adding it forces a fresh registration and sign-in. To clear only the credential, remove and re-add the entry, or use the sign-out control the server row offers in your build.

Verification record

Tier 1 needs a recorded transcript from an installed client. Until then, this page documents configuration only, and the automatic-registration question above stays open.