Local-first knowledge backend for AI agents.
Connect any MCP host — Claude Code, Cursor, or your own agent harness — to a personal knowledge engine: an Obsidian-compatible wiki with indexed retrieval, token-budgeted memory recall, and secure ingestion. Your agents get quality context; you keep your knowledge on your machine.
┌────────────┐ MCP (stdio/sse) ┌───────────────────────────────┐
│ Your agent │ ◄─────────────────► │ Brainstem │
│ (Claude │ 27 tools │ · search + read + write wiki │
│ Code, │ (12 read-only) │ · memory tree recall (BM25 + │
│ Cursor…) │ │ vectors, token-budgeted) │
└────────────┘ │ · code graph over your repos │
│ · vault = plain Markdown │
└───────────────────────────────┘
# Run without installing (recommended)
uvx brainstem-mcp init
# Or install
pip install brainstem-mcp
brainstem initbrainstem init creates a vault at ~/.brainstem/vault (override with
--root) and prints the exact one-liner to connect your agent:
claude mcp add brainstem -- uvx brainstem-mcp mcp --root ~/.brainstem/vaultThat's it. No API key is required to serve, search, and read — your agent brings its own model.
docker build -t brainstem .
docker run -i -v ~/.brainstem/vault:/vault brainstem # stdio
docker run -p 8765:8765 -v ~/.brainstem/vault:/vault brainstem \
mcp --root /vault --transport sse # sse- Search & read —
search_wiki_index,read_wiki_file, cross-references, orphan detection over a plain-Markdown Obsidian-compatible vault. - Remember & recall — a hierarchical memory tree with BM25 + vector search
and token-budgeted
memory_tree_recall, built for agent context windows. - Write knowledge — structured pages with YAML frontmatter, index upkeep, supersession instead of duplication.
- Understand code — ingest a repository and query its architecture
(
ask_repo, code-graph overview/impact) as part of your agent's context.
Expose only the 12 safe read tools (no writes, no publishing):
brainstem mcp --readonlyBrainstem treats everything it ingests as untrusted input: ingested content cannot trigger writes or publishing on its own, and outbound actions are draft-only by design. The vault is plain Markdown on your disk — no cloud, no telemetry, single-tenant by architecture.
OpenWiki generates documentation that agents read as files. Brainstem is a live backend: your agent queries an indexed knowledge base through MCP tools at run time — retrieval, memory, and ingestion as part of the harness, not a batch-generated artifact.
MIT