Connect an agent (MCP)

The Penumbra MCP server lets an AI agent (Claude Code, Claude Desktop, Cursor) operate your graph directly: search, capture, traverse, and read, without writing code. It is the agent-facing counterpart to the SDK, and it is governed by the same shapes and delta membrane. There are three ways into Penumbra, and this is the one for agents:

Surface	For
SDK	Code
Penumbra MCP (this page)	An AI agent operating your graph
Shapes Workbench MCP	Designing shapes

Endpoint

https://mcp.getpenumbra.ai/sse

Authenticate

The server uses OAuth: your client opens a browser consent flow and Penumbra issues a token for the session. You do not put a key in the config.

Add it to your client

Claude Code
Claude Desktop / JSON

claude mcp add --transport sse penumbra https://mcp.getpenumbra.ai/sse

Run a Penumbra tool and the client walks you through the browser login.

{
  "mcpServers": {
    "penumbra": {
      "url": "https://mcp.getpenumbra.ai/sse"
    }
  }
}

What the agent can do

Once connected, the agent has tools to search your graph, capture entities, traverse relationships, and read sources, governed by your shapes. Writes stage through the delta membrane, the same as the SDK. This is what powers the research a domain guide: an agent researches a topic and captures findings straight into your graph.

​Endpoint

​Authenticate

​Add it to your client

​What the agent can do

Endpoint

Authenticate

Add it to your client

What the agent can do