FAQ
Frequently asked questions about Brain Server — the local-first semantic-memory and knowledge-graph server for AI agents.
General
What is Brain Server? A local-first semantic-memory and knowledge-graph server for AI agents. It gives an agent a second brain that lives on the operator’s own device — private, offline-capable, deterministic, and free to run.
Is it really free? Yes — zero per-query cost. Recall uses a static, local embedding model and a deterministic pipeline. There is no LLM or embedding API charged on every read and write. Token accounting: 0 decision tokens, 0 embedding tokens.
Where does my data live? On your device. There is no cloud and no telemetry to third parties. Outbound HTTP is opt-in and off unless configured (an Art 19 DSAR webhook and an optional system-alert webhook).
What does it run on? Anything Rust compiles to. It’s designed for 4 GB ARM edge devices (Jetson Nano, Raspberry Pi 5, a mini PC) drawing under 5 watts, but it runs on any macOS/Linux host.
Usage
How do I install it?
Build from source with cargo build --release --features bench, run ./target/release/brain-server, and hit http://localhost:8765. See the Quickstart.
How do I add memory?
Ingest markdown with POST /ingest/markdown, structured data with POST /ingest, or memories with POST /ingest/memory. [[relation::entity]] links build the knowledge graph.
How do I recall?
Call POST /recall with a QueryDoc, or use brain query "...". See Retrieval & Recall.
Is there a GUI?
Yes — a Dioxus web + desktop + mobile app served at /app. See the Client GUI.
Does it work with OpenClaw?
Yes — Brain Server is the memory backend for OpenClaw via a kind: "memory" plugin. See the OpenClaw Integration page.
Capability
Does it use an LLM?
No. Retrieval, graph building, classification, and span verification are all deterministic — no LLM in the loop. Static embeddings via model2vec.
Can it say “I don’t know”?
Yes. Calibrated abstention: when retrieval quality is too low, /recall returns {decision: "low_confidence", hits: []} instead of top-1 garbage.
Can it forget?
Yes, deliberately and auditably. POST /purge deletes by id/owner with a tombstone + audit row; the DSAR workflow locates, exports, purges, and issues a chain-verifiable deletion certificate. Nothing is deleted autonomously.
Can I see why a result was returned?
Yes. Every result carries provenance, and /recall?trace=true records a replayable decision path. See Retrieval & Recall.
Security & compliance
How is it secured? Loopback-safe by default; two auth modes (opaque bearer or JWT/JWS); a deny-by-default AuthZ layer; an append-only SHA-256 audit chain. See Security.
Is it compliant? It maps to ISO/IEC 42001, NIST AI RMF, SOC 2, GDPR, CCPA/CPRA, and the Philippines DPA — as a documented engineering posture, not a certification. See Governance & Compliance.
Where do I report a vulnerability? Use the GitHub Security Advisories tab. Do not file public issues for security findings.
Troubleshooting
I get exit 137 on first run (macOS).
A com.apple.provenance xattr makes Gatekeeper SIGKILL freshly copied executables. Use scripts/install-service.sh — it strips the xattr. See Installation.
The server won’t bind 0.0.0.0.
By design. Set BIND_PUBLIC=1 to bind publicly. See Configuration.
Next steps
- Quickstart — get running.
- Glossary — terminology.
- Contributing — how to help.