Claude Engram

Persistent memory and session intelligence for AI coding assistants. Hooks into Claude Code's lifecycle to auto-track mistakes, decisions, and context — then mines your full session history to surface patterns, predict what you'll need, and search across everything you've ever discussed.

Zero manual effort. Works with any MCP-compatible client.

What It Does

Automatic (hooks — zero invocation):

• Tracks every edit, error, test result, and session event
• Auto-captures decisions from your prompts ("let's use X", "switch to Y")
• Injects the 3 most relevant memories before every file edit
• Warns when you're about to repeat a past mistake
• Detects edit loops (same file 3+ times without progress)
• Survives context compaction — checkpoints before, re-injects after
• Mines your session history in the background after every session

Session Mining (automatic, background):

• Parses Claude Code's full conversation logs (JSONL) after every session — including subagent conversations (Explore, Plan, code-reviewer, etc.)
• Extracts decisions, mistakes, approaches, and user corrections using structural analysis + AllMiniLM semantic scoring (typo-tolerant)
• Builds a searchable index across all past conversations (20k+ chunks with subagents)
• Detects recurring struggles, error patterns, and file edit correlations
• Predicts what files and context you'll need before edits
• Reflects on patterns using local LLM to synthesize root causes and architectural insights
• On first install, retroactively mines your entire session history

On-demand (MCP tools):

• memory — store, search, archive, and manage memories
• session_mine — search past conversations, find decisions, replay file history, detect patterns
• work — log decisions and mistakes with reasoning
• Plus: scope guard, context checkpoints, convention tracking, impact analysis

How It Works

Claude Code
    |
    +-- Hooks (remind.py)                    <- Intercepts every tool call
    |   SessionStart / Edit / Bash / Error / Compact / Stop
    |
    +-- Session Mining (mining/)             <- Background intelligence
    |   JSONL parser -> Extractors -> Search index -> Pattern detection
    |
    +-- MCP Server (server.py)              <- Tools for manual operations
    |   memory, session_mine, work, scope, context, ...
    |
    +-- Scorer Server (scorer_server.py)    <- Persistent AllMiniLM process
        TCP localhost, ~90MB RAM, batch embeddings

Hooks fire on every tool call (1-2s budget each). Heavy processing happens in a background subprocess after session end. The scorer server stays loaded in memory for fast semantic scoring.

Benchmarks

Integration benchmarks

These test what the product actually does.

Benchmark	What it tests	Result
Decision Capture (220 prompts)	Auto-detect decisions from user prompts	97.8% precision, 36.7% recall
Injection Relevance (50 memories, 15 cases)	Right memories surface before edits	14/15 passed, 100% isolation
Compaction Survival (6 scenarios)	Rules/mistakes survive context compression	6/6
Error Auto-Capture (53 payloads)	Extract errors, reject noise, deduplicate	100% recall, 97% precision
Multi-Project Scoping (11 cases)	Sub-project isolation + workspace inheritance	11/11
Edit Loop Detection (12 scenarios)	Detect spirals vs iterative improvement	12/12
Session Mining (27 tests)	JSONL parsing, indexing, search, incremental processing	27/27
Obsidian Vault (25 tests)	Compatibility with PARA + CLAUDE.md vault structure	25/25

Reproduce: python tests/bench_integration.py, bench_session_mining.py, bench_obsidian_vault.py

Retrieval benchmarks

Retrieval-only (recall@k) — whether the right memory is found in top results.

Benchmark	Score
LongMemEval Recall@5 (500 questions)	0.966
LongMemEval Recall@10	0.982
ConvoMem (250 items, 5 categories)	0.960
LoCoMo R@10 (1,986 questions)	0.649
Speed	43ms/query
Cross-session search	112ms/query over 7310 chunks

Reproduce: python tests/bench_longmemeval.py, bench_locomo.py, bench_convomem.py

Compatibility

Platform	What Works	Auto-Capture
Claude Code (CLI, desktop, VS Code, JetBrains)	Everything	Full — hooks + session mining
Cursor	MCP tools (memory, search, etc.)	No hooks
Windsurf	MCP tools	No hooks
Continue.dev	MCP tools	No hooks
Zed	MCP tools	No hooks
Any MCP client	MCP tools	No hooks
Obsidian vaults	Full (with CLAUDE.md at root)	Full with Claude Code

Install

git clone https://github.com/20alexl/claude-engram.git
cd claude-engram
python -m venv venv
source venv/bin/activate  # or venv\Scripts\activate on Windows

pip install -e .                # Core
pip install -e ".[semantic]"    # + AllMiniLM for vector search and semantic scoring

python install.py               # Configure hooks, MCP server, and /engram skill

Per-Project Setup

python install.py --setup /path/to/your/project

Or copy .mcp.json to your project root.

Note: The CLAUDE.md in this repo is engram-specific documentation — it's not required for engram to work. Hooks fire automatically and the /engram skill provides a quick reference on demand. If you already have a CLAUDE.md for your project, keep it as-is and don't copy ours over it. If you want engram docs alongside your project rules, rename it to CLAUDE-ENGRAM.md (or similar) so it doesn't clobber your existing file — Claude will see it when relevant.

Updating

cd claude-engram
git pull
pip install -e ".[semantic]"    # Reinstall if dependencies changed
python install.py               # Re-run to update hooks and /engram skill

Hooks and MCP tools pick up code changes immediately (editable install). Reconnect the MCP server in Claude Code (/mcp) to reload the server process.

Mid-Project Adoption

Already deep in a project? Install normally. On first session, engram auto-detects your existing Claude Code session history and mines it in the background — extracting decisions, mistakes, and patterns from all past conversations. No manual effort.

Key Features

Memory System

• Hybrid search — keyword + AllMiniLM vector + reranking. No ChromaDB.
• Scored injection — top 3 memories by file match, tags, recency, importance before every edit.
• Tiered storage — hot (fast) + archive (cold, searchable, restorable). Rules and mistakes never archive.
• Multi-project — memories scoped per sub-project. Workspace rules cascade down.

Session Mining

• Structural extraction — analyzes conversation flow (confirmations, redirects, error->fix sequences, approach changes) instead of template matching.
• Tool content indexing — bash commands + output, edit diffs, and error tracebacks are searchable alongside conversation text.
• Batch embeddings — 22x faster than individual calls via batched TCP protocol.
• Cross-session search — 44k+ conversation chunks indexed, semantic + keyword + hybrid search.
• Pattern detection — recurring struggles, error patterns, edit correlations across sessions.
• Predictive context — before edits, surfaces related files and likely errors from history.
• Cross-project learning — aggregates patterns across all your projects.
• Retroactive bootstrap — mines all existing session history on first install.
• Scorer auto-start — AllMiniLM server starts on demand if not running. No silent degradation.

Lifecycle

• Auto-captures decisions — structural patterns (confirmations, redirects, explicit choices) + semantic scoring as bonus.
• Auto-tracks mistakes from any failed tool. Only logs errors in project files (filters transient noise). Warns before repeat edits.
• Survives compaction — checkpoints with session decisions/mistakes, re-injects after.
• Edit loop detection — flags when the same file is edited 3+ times without progress.

Configuration

Variable	Default	Description
CLAUDE_ENGRAM_MODEL	gemma3:12b	Ollama model (optional — only for scout_search, convention checking)
CLAUDE_ENGRAM_ARCHIVE_DAYS	14	Days until inactive memories archive
CLAUDE_ENGRAM_SCORER_TIMEOUT	1800	AllMiniLM server idle timeout (seconds)

Reindexing

If search quality is poor or you want to rebuild after an update:

python scripts/reindex.py "E:\workspace" --force            # rebuild search index
python scripts/reindex.py "E:\workspace" --force --extract   # also re-extract decisions/mistakes

Or via MCP: session_mine(operation="reindex", mode="bootstrap")

Documentation

Library Book — design philosophy, internals, full usage guide, API reference, gotchas, and changelog.

/engram — slash command with quick tool reference (installed by install.py).

License

MIT