Extension Catalog

Extensions for the-brain — swap any layer, harvest from any AI tool, train however you want. Mix and match.

🧪 The extensions below are our research starter pack — what ships today. Community extensions coming. Build yours →

🔍 Browse by Layer

Filter packages by the cognitive layer they operate on.

• ⚡ Instant
• ⚖️ Selection
• 🌌 Deep
• 📥 Harvesters
• 🔧 Infrastructure

⚡ Instant Layer

Real-time context injection — corrections, preferences, and patterns detected immediately.

@the-brain-dev/plugin-graph-memory

• Version: v0.1.0
• Type: Memory
• Status: Starter pack
• Description: Creates fast relational nodes of recent corrections. Language-agnostic structural heuristics with weight boost on match and weight decay for stale nodes.

⚖️ Selection Layer

The Gatekeeper — filters noise from signal. Only surprising, high-value memories are promoted to deep storage.

@the-brain-dev/plugin-spm-curator

• Version: v0.1.0
• Type: Memory
• Status: Starter pack
• Description: Surprise-Gated Prediction Error filter. Composite surprise score using scalar, embedding, and novelty metrics. Configurable threshold (default: 0.30).

🌌 Deep Layer

Permanent consolidation — overnight LoRA training, identity anchoring, and knowledge wiki generation.

@the-brain-dev/trainer-local-mlx

• Version: v0.1.0
• Type: Trainer
• Status: Starter pack (macOS only)
• Description: Runs overnight at 2 AM. Trains LoRA adapters on consolidated DEEP memories. Fully local — data never leaves your machine. Requires Apple Silicon + uv.

@the-brain-dev/plugin-identity-anchor

• Version: v0.1.0
• Type: Memory
• Status: Starter pack
• Description: Maintains a stable self-vector across LoRA retrains. Detects drift in coding style and preferences.

@the-brain-dev/plugin-auto-wiki

• Version: v0.1.0
• Type: Output
• Status: Starter pack
• Description: Weekly static wiki output from consolidated knowledge. Interlinked markdown pages with concept nodes and entity pages.

📥 Harvesters

Harvesters — collect interactions from any AI tool and push them into the pipeline.

@the-brain-dev/plugin-harvester-cursor

• Version: v0.1.0
• Type: Harvester
• Status: Starter pack
• Description: Reads Cursor's local SQLite workspace database. Auto-detects project context via workDir matching.

@the-brain-dev/plugin-harvester-claude

• Version: v0.1.0
• Type: Harvester
• Status: Starter pack
• Description: Reads Claude Code's local JSONL conversation logs. Tracks offset/checkpoint to avoid re-processing.

@the-brain-dev/plugin-harvester-gemini

• Version: v0.1.0
• Type: Harvester
• Status: Starter pack
• Description: Polls Gemini CLI's local JSON logs for new interactions.

@the-brain-dev/plugin-harvester-hermes

• Version: v0.1.0
• Type: Harvester
• Status: Starter pack
• Description: Polls Hermes Agent's SQLite state.db for user↔assistant chat interactions.

@the-brain-dev/plugin-harvester-lm-eval

• Version: v0.1.0
• Type: Harvester
• Status: Starter pack
• Description: Harvests lm-evaluation-harness benchmark results. Computes per-model per-benchmark fingerprints with anomaly detection (>2σ). Enables the-brain as cognitive layer for meta-harness systems (AHE, Meta-Harness).

🔧 Infrastructure

Core framework, integrations, and storage backends.

@the-brain-dev/core

• Version: v0.1.0
• Type: Core
• Status: Starter pack
• Description: Empty data bus — everything else is a plugin via definePlugin(). Includes hook system, BrainDB (Drizzle ORM + sqlite), LayerRouter, ProjectManager, ContentCleaner, AuthDB (multi-user auth), and PermissionResolver.

@the-brain-dev/mcp-server

• Version: v0.1.0
• Type: Integration
• Status: Starter pack
• Description: MCP (Model Context Protocol) server — exposes the-brain as a memory backend for Claude Desktop, Cursor, Zed. 26 tools + 11 resources + SSE subscriptions + meta-harness integration tools.

@the-brain-dev/storage-libsql

• Version: v0.1.0
• Type: Storage
• Status: Starter pack (optional)
• Description: Alternative to SQLite. Enables shared database across multiple servers for team deployments via Turso.

Architecture Overview

📥 Harvesters  →  ⚡ Instant Layer  →  ⚖️ Selection Layer  →  🌌 Deep Layer  →  🔌 Clients

cursor          graph-memory         spm-curator             trainer-local-mlx     MCP Server
claude                                (surprise filter)      identity-anchor       Claude Desktop
gemini                                                       auto-wiki             Cursor, Zed
hermes                                                       lm-eval harvester     AHE, Meta-Harness
lm-eval                                                      (benchmark data)      (via MCP tools)

Building Your Own Plugin

See Writing Plugins for the full plugin authoring guide.

Extension Commands

Extensions register custom commands accessible via the-brain ext <cmd>:

# List all registered extension commands
the-brain ext --list

⚠️ Limitation: brain.registerCommand() registers commands in the daemon process memory. The CLI process (the-brain ext) has its own copy and can't see daemon-registered commands. For extensions that need CLI access, use a standalone runner script (see Writing Plugins for the pattern).