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Judgment MCP server

Give coding agents authenticated access to Judgment project data and tools.

The Judgment MCP server gives coding agents authenticated, project-scoped tools for investigating traces, inspecting evaluations, and performing approved actions.

Connect the Judgment MCP server

Prerequisites

  • A Judgment account with access to at least one organization and project.
  • Cursor, Claude Code, Windsurf, or Codex with remote HTTP MCP support.
  • For the API-key fallback, a key from Settings → Account & API Key

Add the data MCP

Use browser-based OAuth when your client supports it. The client stores the resulting access token; do not add an API key to its configuration. During authorization, choose the intended organization and leave Project set to All Projects in This Organization for this tutorial. A project-specific grant intentionally hides cross-project discovery tools.

Add the server to ~/.cursor/mcp.json for every workspace, or .cursor/mcp.json for this project:

{
  "mcpServers": {
    "judgment": {
      "url": "https://mcp.judgmentlabs.ai"
    }
  }
}

Open Cursor’s MCP settings, select judgment, and complete Sign in in the browser when prompted.

Add the remote HTTP server:

claude mcp add --transport http judgment https://mcp.judgmentlabs.ai

Claude Code opens the browser authorization flow when it first connects.

Add the server to ~/.codeium/windsurf/mcp_config.json:

{
  "mcpServers": {
    "judgment": {
      "serverUrl": "https://mcp.judgmentlabs.ai"
    }
  }
}

Open Windsurf’s MCP settings and complete the browser sign-in prompt for judgment.

Cascade can expose at most 100 total tools at one time. If a tool from the MCP reference is not visible, open the Judgment MCP settings and toggle tool availability so the tools needed for the task are enabled.

Add the remote HTTP server, then start its OAuth login:

codex mcp add judgment --url https://mcp.judgmentlabs.ai
codex mcp login judgment

Complete authorization in the browser. The equivalent configuration is:

[mcp_servers.judgment]
url = "https://mcp.judgmentlabs.ai"

Use an API key only when OAuth is unavailable

Store the key in an environment variable and configure the client to send it as Authorization: Bearer <key>. For example, Codex can read the token without placing it in config.toml:

export JUDGMENT_API_KEY="<your-api-key>"
codex mcp add judgment \
  --url https://mcp.judgmentlabs.ai \
  --bearer-token-env-var JUDGMENT_API_KEY

Cursor and Windsurf also accept an Authorization header in their server JSON. Claude Code accepts one with --header. Keep the value out of tracked project files, shell history, logs, and prompts. See Authentication for the shared credential model.

Verify organization and project access

Restart or reload the client after changing its MCP configuration, then ask:

Use the Judgment MCP tools. Call list_organizations, choose the organization
named <organization-name>, then call list_projects for its organization_id.
Return the selected organization_id and the project_id for <project-name>.
Do not make any changes.

Success means the answer contains the real organization_id returned by list_organizations and the real project_id returned by list_projects. If either name is missing, confirm that the signed-in user or API key belongs to the intended organization and that the project exists there.

Next, install the Judgment agent skill so the coding agent knows the recommended investigation workflow, or use the MCP tools reference for exact tool names and input fields.

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