Install

Recommended door: the agent bootstrap. Open your agent (Codex, Claude Code, or any harness) in the folder that will become its home and paste the block from the README's install section — the agent fetches BOOTSTRAP_FOR_AGENTS.md from the latest-stable tag, installs the CLI, initializes a local PGLite brain, wires MCP, and isn't done until gbrain bootstrap verify exits 0. Full contract, security posture, and uninstall: docs/guides/bootstrap.md.

The paths below are the manual equivalents and deep-dive detail. Pick one. Mix later if needed.

1. Run with an agent platform

Already running OpenClaw or Hermes?

bun install -g github:garrytan/gbrain#latest-stable
gbrain init --pglite                  # 2 seconds; no server
gbrain skillpack scaffold --all       # scaffolds every bundled skill (skills/manifest.json) into your agent workspace
gbrain doctor                         # green checks all the way down

Your agent now reads skills/RESOLVER.md once per request, routes intent to the right skill, executes. New entity mentions create new pages. Daily cron runs enrichment overnight.

Scaffolded skills are first-class files in your agent repo — edit freely. To pull upstream gbrain improvements later, gbrain skillpack reference <name> diffs your local copy vs the bundle. The legacy skillpack install managed-block model was retired in v0.36.0.0; if you're upgrading from an older release, run gbrain skillpack migrate-fence once to strip the legacy fence and keep your existing skill rows.

To upgrade later: gbrain upgrade runs schema migrations + post-upgrade prompts (chunker bumps, provider-sunset notices). Always TTY-only; non-TTY upgrades skip prompts with informational stderr lines.

2. CLI standalone

No agent platform, just shell + MCP-aware editor.

bun install -g github:garrytan/gbrain#latest-stable
gbrain init --pglite

If bun install -g hits a postinstall error (Bun blocks postinstall hooks in some environments), the CLI prints a recovery hint pointing at #218. Run gbrain doctor to diagnose, then gbrain apply-migrations --yes manually. The deterministic fallback is git clone https://github.com/garrytan/gbrain.git ~/gbrain && cd ~/gbrain && bun install && bun link.

The init flow detects your repo size and suggests Supabase for brains > 1000 markdown files. To switch later:

gbrain migrate --to supabase     # PGLite → Postgres
gbrain migrate --to pglite       # Postgres → PGLite (rare)

For shared / large / multi-machine deployments (a team or company brain with multiple users hitting one server over HTTP MCP with OAuth scoping per user), follow the dedicated walkthrough: Tutorial: set up GBrain as your company brain.

API keys live in ~/.gbrain/config.json (file plane) or env vars (VOYAGE_API_KEY, OPENAI_API_KEY, OPENROUTER_API_KEY, ANTHROPIC_API_KEY). Set them via env or by editing ~/.gbrain/config.json directly — do NOT use gbrain config set for API keys (that writes the DB plane, which the embedding pipeline never reads):

export VOYAGE_API_KEY=pa-...          # default embedding (voyage-4) + reranker (rerank-2.5) — one key
export OPENAI_API_KEY=sk-...          # alternative embeddings; also powers automatic fact extraction + chat models
export ANTHROPIC_API_KEY=sk-ant-...   # automatic fact extraction + chat models; also improves search via query expansion

Chat-shaped features (automatic fact extraction, enrichment, synthesis, query expansion) route to whichever supported chat key is present (Anthropic or OpenAI) — Anthropic when both are set, OpenAI when it is the only one; other chat providers need an explicit models.* pin. With neither key, they stay off calmly and memory comes from agent-authored ## Facts fences and the remember verb.

ZEROENTROPY_API_KEY is still honored but deprecated — the ZeroEntropy hosted API shuts down 2026-09-04. Off-ramp: the agent playbook at skills/migrations/v0.46.3.0.md (one command migrates embeddings + reranker) with the full reference in docs/guides/embedding-migration.md.

Common follow-ups:

gbrain import ~/my-knowledge      # bulk-import a markdown folder
gbrain sync --watch               # live-sync a git repo (autopilot mode)
gbrain autopilot --install        # background daemon for nightly enrichment

Wire this same local brain into your coding agent — zero server, zero token:

claude mcp add gbrain -- gbrain serve --surface verbs    # Claude Code
codex  mcp add gbrain -- gbrain serve --surface verbs    # Codex

The agent spawns gbrain serve as a stdio subprocess against your local brain. --surface verbs gives the agent the seven-verb memory protocol (recall, remember, entity, synthesize, forget, context_pack, delta — MEMORY_VERBS v1) instead of the full tool catalog; --surface starter adds the daily-driver set on top of the verbs (~27 ops total); drop the flag (default full) for every operation. Full walkthrough (both this local path and connecting to a remote brain), plus the brain-first protocol to paste into CLAUDE.md / AGENTS.md: Give your coding agent a memory.

3. MCP server (any MCP client)

gbrain serve                      # stdio MCP (Claude Desktop / Code / Cursor)
gbrain serve --surface verbs      # stdio MCP, just the 7 memory verbs (quickstart)
gbrain serve --http               # HTTP MCP with OAuth 2.1 + admin dashboard

Wire a coding agent to a remote brain in one command (when you have an HTTP server + a bearer token): gbrain connect prints a paste-ready setup block, or --install runs it and smoke-tests the token.

gbrain auth create "claude-code"
gbrain connect https://your-host/mcp --token gbrain_xxx                      # Claude Code (default)
gbrain connect https://your-host/mcp --token gbrain_xxx --agent codex        # Codex (env-var bearer)
gbrain connect https://your-host/mcp --agent perplexity --oauth --register   # Perplexity (OAuth)

Per-client setup guides live in docs/mcp/:

docs/mcp/CLAUDE_CODE.md
docs/mcp/CODEX.md
docs/mcp/CLAUDE_DESKTOP.md
docs/mcp/CHATGPT.md
docs/mcp/PERPLEXITY.md
docs/mcp/HERMES.md — Hermes (Nous Research CLI)
docs/mcp/GROK.md — Grok Build (xAI CLI)
docs/mcp/OPENCODE.md — opencode (opencode.ai / SST terminal agent)
docs/mcp/OPENCLAW.md — OpenClaw (bundle plugin or stdio)
docs/mcp/CLAUDE_COWORK.md — Claude Cowork (team plan)
docs/mcp/DEPLOY.md — production deploy patterns

The HTTP server ships with an admin SPA at /admin, an SSE activity feed at /admin/events, DCR-style client registration, scope-gated read/write/admin access, and rate limiting.

Thin-client mode

Connect to someone else's brain without running a local engine:

gbrain init --mcp-only            # configures remote MCP, skips local DB

Useful for: team mounts, brain-as-a-service deployments, dev machines without disk space. Most local commands refuse with a paste-ready hint. See docs/architecture/topologies.md.

Verifying the install

gbrain bootstrap verify           # the whole install contract; exits non-zero on failure
gbrain doctor --json              # full health check
gbrain models                     # which AI models are configured for what
gbrain models doctor              # 1-token probe per configured model

If anything's yellow, gbrain doctor names the fix command in the message. Most issues are missing API keys or stale schema (gbrain upgrade --force-schema). For the manual check-by-check runbook, see docs/GBRAIN_VERIFY.md.

Troubleshooting

PGLite crashes at startup (`RuntimeError: Aborted()`)

This crash (typically first seen after a macOS upgrade) is not a macOS/WASM incompatibility — an unclean shutdown tore the data dir's write-ahead log, and every subsequent open fails WAL replay. The short version of the recovery ladder:

Auto-repair (default): run any gbrain command — gbrain detects the abort, resets the WAL in place (data preserved, backup kept), and continues. Then run gbrain doctor.
Manual repair: gbrain pglite-repair --dry-run, then gbrain pglite-repair --yes.
Rebuild: gbrain reinit-pglite.
Switch engines: Supabase or native Homebrew Postgres + pgvector.

The full ladder — safety bounds, kill-switches, when WAL repair can't help, and the Homebrew Postgres recipe — lives in docs/ENGINES.md.

INSTALL