@Littlebigbrain/

Eleven task-shaped MCP tools for searching, querying, and writing a little big brain graph from Claude, Cursor, Codex, or another MCP client.

Hosted OAuth

Use the hosted endpoint; the client opens WorkOS sign-in and your machine never stores a little big brain stack key:

{
  "mcpServers": {
    "lbb": {
      "url": "https://mcp.littlebigbrain.com/mcp/<stack-slug>"
    }
  }
}

Codex Desktop should use the origin plus a stack header:

{
  "mcpServers": {
    "lbb": {
      "type": "http",
      "url": "https://mcp.littlebigbrain.com",
      "headers": { "X-LBB-Stack": "<stack-slug>" }
    }
  }
}

Local stdio

{
  "mcpServers": {
    "lbb": {
      "command": "npx",
      "args": ["-y", "@littlebigbrain/mcp"],
      "env": {
        "LBB_BASE_URL": "https://db.eu.littlebigbrain.com",
        "LBB_API_KEY": "lbb_sk_live_..."
      }
    }
  }
}

Set LBB_GRAPH or LBB_BRANCH when the scope is not main.

Tools

Tool	Use it for
lbb_search	hybrid retrieval, multi-query fusion, optional path following
lbb_ask	grounded answers with citations
lbb_decode	constrained relation decoding
lbb_ground	vocabulary completion and resolution
lbb_inspect	ontology, entity, state, history, provenance, traversal
lbb_query	SPARQL, structured analytics, SHACL, inference
lbb_commit	facts, properties, and embeddings
lbb_observe	conversation episodes plus reviewed extraction
lbb_branch	isolation branches and validated merge
lbb_configure	ontology, schema, and inference rules
lbb_index	BM25, vector, and adjacency refresh

Read tools return compact structured envelopes by default. Use detail, row_limit, and returned cursors to page without silently truncating results. Write tools derive idempotency keys unless you provide one.

Embed the server

import { createMcpHttpServer } from "@littlebigbrain/mcp";

createMcpHttpServer({
  baseUrl: "https://db.eu.littlebigbrain.com",
  mcpPath: "/mcp",
  allowedHosts: ["127.0.0.1", "localhost", "::1", "[::1]"],
}).listen(8080, "127.0.0.1");

The embedded HTTP server passes a key bearer to the database and is for self-hosting behind your own auth. The hosted endpoint's OAuth/ownership layer is served by the little big brain API.

Full tool schemas and examples: MCP documentation.