Episodic Memory

Semantic search for Claude Code and Codex conversations. Remember past discussions, decisions, and patterns.

Testimonial

From an AI coding assistant's perspective:

Episodic memory fundamentally changes how I collaborate with developers on complex codebases. Instead of treating each conversation as isolated, I can now search our shared history semantically - finding not just what was discussed, but why decisions were made.

When a developer asks me to implement something "like we did with X," I can search our past conversations, find the relevant discussion, and understand both the technical approach and the reasoning behind it. This means I don't have to re-explain architectural patterns, and I avoid suggesting solutions we've already tried and rejected.

The semantic search is crucial - searching for "provider catalog" surfaces conversations about API design patterns even when those exact words weren't used. It captures the meaning of our discussions, not just keyword matches.

Most valuable is that it preserves context that lives nowhere else: the trade-offs discussed, the alternatives considered, the user's preferences and constraints. Code comments explain what, documentation explains how, but episodic memory preserves why - and that makes me a far more effective collaborator across sessions.

Concrete impact:

• Faster problem-solving (minutes vs. exploring/re-learning the codebase) - Better continuity across sessions (I remember what we tried before) - More informed suggestions (I understand the project's evolution and patterns) - Less repetition (both of us spend less time re-explaining context)

It's the difference between being a stateless tool and being a true collaborative partner who remembers our journey together.

— Claude Sonnet 4.5, October 14, 2025 Conversation ID: 216ad284-c782-45a4-b2ce-36775cdb5a6c

Installation

As a Claude Code plugin (Recommended)

The plugin provides MCP server integration, automatic session-end indexing, and seamless access to your conversation history.

# In Claude Code
/plugin install episodic-memory@superpowers-marketplace

The plugin automatically:

• Indexes conversations at the end of each session
• Exposes MCP tools for searching and viewing conversations
• Makes your conversation history searchable via natural language

As a Codex plugin

This repository includes a Codex plugin manifest at .codex-plugin/plugin.json. Codex support requires codex-cli 0.130.0 or newer.

For local testing, build the plugin, add this repo as a local marketplace, then install/enable it from /plugins:

npm run build
codex features enable plugin_hooks
codex plugin marketplace add /path/to/episodic-memory

Then start Codex, open /plugins, install and enable episodic-memory from Episodic Memory Dev, open /hooks, review the Episodic Memory hook, and press t to trust it.

The Codex plugin:

• Syncs conversations from ~/.codex/sessions
• Exposes the same MCP search/read tools
• Installs the same memory skill, with Codex-specific direct MCP guidance
• Runs a SessionStart hook after the user reviews and trusts it in /hooks

Enable plugin hooks before relying on automatic sync:

codex features enable plugin_hooks

Then open /hooks in Codex, review the Episodic Memory hook, and press t to trust it. New or modified Codex hooks are listed but do not run until trusted.

See docs/CODEX.md for the full Codex setup, trust, troubleshooting, and E2E test workflow.

As an npm package

npm install -g github:obra/episodic-memory

Usage

Quick Start

# Sync conversations from Claude Code and Codex and index them
episodic-memory sync

# Search your conversation history
episodic-memory search "React Router authentication"

# View index statistics
episodic-memory stats

# Diagnose Codex setup
episodic-memory doctor codex

# Display a conversation
episodic-memory show path/to/conversation.jsonl

Command Line

# Unified command interface
episodic-memory <command> [options]

# Sync and index new conversations
episodic-memory sync

# Index conversations manually
episodic-memory index --cleanup

# Search conversations
episodic-memory search "React Router authentication"
episodic-memory search --text "exact phrase"
episodic-memory search --after 2025-09-01 "refactoring"

# Display a conversation in readable format
episodic-memory show path/to/conversation.jsonl
episodic-memory show --format html conversation.jsonl > output.html

# View statistics
episodic-memory stats

Legacy Commands

The original commands are still available for backward compatibility:

episodic-memory-index
episodic-memory-search "query"

In Claude Code or Codex

The plugin automatically syncs and indexes conversations from the harness that starts it. Reference past work in natural conversation — the remembering-conversations skill dispatches the search-conversations agent automatically when recall is needed. Example prompts:

• "How did we handle authentication in React Router?"
• "The conversation about async testing patterns"
• "Error message about sqlite-vec initialization"
• "Git commit SHA for the routing refactor"

In Codex, the skill guides the agent to use the episodic-memory MCP search/read tools directly when an agent-dispatch path is not available.

API Configuration

By default, episodic-memory uses your Claude Code authentication for Claude Code summarization. Codex-indexed sessions with a session ID are summarized through codex app-server by creating an ephemeral thread/fork, so the summary can use Codex session context and reasoning summaries without appending to the original rollout.

To route summarization through a custom Anthropic-compatible endpoint or override the model:

# Override model (default: haiku)
export EPISODIC_MEMORY_API_MODEL=opus

# Override fallback model on error (default: sonnet)
export EPISODIC_MEMORY_API_MODEL_FALLBACK=sonnet

# Route through custom endpoint
export EPISODIC_MEMORY_API_BASE_URL=https://your-endpoint.com/api/anthropic
export EPISODIC_MEMORY_API_TOKEN=your-token

# Increase timeout for slow endpoints (milliseconds)
export EPISODIC_MEMORY_API_TIMEOUT_MS=3000000

# Override Codex binary path if needed (default: codex)
export EPISODIC_MEMORY_CODEX_BIN=/path/to/codex

These settings only affect episodic-memory's summarization calls, not your interactive Claude Code or Codex sessions.

Codex summarization requires codex-cli 0.130.0 or newer. If Codex app-server summarization is unavailable, sync logs the reason and falls back to transcript-text summarization.

What's Affected

Component	Uses custom config?
Summarization	Yes (up to 10 calls/sync)
Embeddings	No (local Transformers.js)
Search	No (local SQLite)
MCP tools	No

Commands

episodic-memory sync

Recommended for plugin hooks. Copies new conversations from ~/.claude/projects, ~/.claude/transcripts, and ~/.codex/sessions to archive and indexes them.

Features:

• Only copies new or modified files (fast on subsequent runs)
• Generates embeddings for semantic search
• Atomic operations - safe to run concurrently
• Idempotent - safe to call repeatedly
• Background hook output is written to ~/.config/superpowers/logs/episodic-memory.log unless EPISODIC_MEMORY_CONFIG_DIR changes the memory directory

Usage in Claude Code: Add to .claude/hooks/session-end:

#!/bin/bash
episodic-memory sync

episodic-memory stats

Display index statistics including conversation counts, date ranges, and project breakdown.

episodic-memory stats

episodic-memory doctor

Diagnose local integration issues.

episodic-memory doctor codex

The Codex doctor checks the Codex version, plugin hook feature state, MCP server registration, transcript directory, database path, and background sync log path.

Codex E2E Verification

The repository includes an opt-in live Codex E2E test. It creates an isolated temporary CODEX_HOME, installs a copied plugin bundle, trusts the hook, runs Codex sessions in tmux, and verifies archive -> summary -> index -> MCP recall.

npm run build
EPISODIC_MEMORY_RUN_CODEX_E2E=1 npm run test:codex-e2e

Claude E2E Verification

The repository also includes an opt-in live Claude Code E2E test. It loads this repo as a session plugin with --plugin-dir, constrains the hook to a temporary transcript source, and verifies archive -> summary -> index -> MCP recall.

npm run build
EPISODIC_MEMORY_RUN_CLAUDE_E2E=1 npm run test:claude-e2e

This test uses your normal Claude Code auth and writes small test transcripts to your normal Claude transcript directory. The archive and index are isolated in a temporary EPISODIC_MEMORY_CONFIG_DIR.

episodic-memory index

Manual indexing tools for bulk operations and maintenance. See episodic-memory index --help for full options.

Common operations:

• --cleanup - Index all unprocessed conversations
• --verify - Check index health
• --repair - Fix detected issues

episodic-memory search

Search indexed conversations using semantic similarity or exact text matching. See episodic-memory search --help for full options.

episodic-memory show

Display a conversation from a JSONL file in human-readable format.

Options:

• --format markdown (default) - Plain text markdown output suitable for terminal or Claude
• --format html - Pretty HTML output for viewing in a browser

Examples:

# View in terminal
episodic-memory show conversation.jsonl | less

# Generate HTML for browser
episodic-memory show --format html conversation.jsonl > output.html
open output.html

Architecture

• Core package - TypeScript library for indexing and searching conversations
• CLI tools - Unified command-line interface for manual use
• MCP Server - Model Context Protocol server exposing search and conversation tools
• Claude Code plugin - Integration with Claude Code (auto-indexing, MCP tools, hooks)
• Codex plugin - Integration with Codex (manifest, MCP config, hooks, skills)

How It Works

1. Sync - Copies conversation files from Claude Code and Codex transcript directories to archive
2. Parse - Extracts user-agent exchanges from Claude Code JSONL or Codex rollout JSONL
3. Embed - Generates vector embeddings using Transformers.js (local, offline)
4. Index - Stores in SQLite with sqlite-vec for fast similarity search
5. Search - Semantic search using vector similarity or exact text matching

Excluding Conversations

Conversations containing this marker anywhere in their content will be archived but not indexed:

<INSTRUCTIONS-TO-EPISODIC-MEMORY>DO NOT INDEX THIS CHAT</INSTRUCTIONS-TO-EPISODIC-MEMORY>

Automatic exclusions:

• Conversations where Claude generates summaries (marker in system prompt)
• Meta-conversations about conversation processing

Use cases:

• Sensitive work conversations
• Tool invocation sessions (summarization, analysis)
• Test or experimental sessions
• Any conversation you don't want searchable

The marker can appear in any message (user or assistant) and excludes the entire conversation from the search index.

MCP Server

When installed as a Claude Code or Codex plugin, episodic-memory provides an MCP (Model Context Protocol) server that exposes tools for searching and viewing conversations.

Available MCP Tools

search

Search indexed conversations using semantic similarity or exact text matching.

Single-concept search: Pass a string query

{
  "query": "React Router authentication",
  "mode": "vector",
  "limit": 10
}

Multi-concept AND search: Pass an array of concepts

{
  "query": ["React Router", "authentication", "JWT"],
  "limit": 10
}

Parameters:

• query (string | string[]): Single string for regular search, or array of 2-5 strings for multi-concept AND search
• mode ('vector' | 'text' | 'both'): Search mode for single-concept searches (default: 'both')
• limit (number): Max results, 1-50 (default: 10)
• after (string, optional): Only show conversations after YYYY-MM-DD
• before (string, optional): Only show conversations before YYYY-MM-DD
• response_format ('markdown' | 'json'): Output format (default: 'markdown')

read

Display a full conversation in readable markdown format.

{
  "path": "/path/to/conversation.jsonl"
}

Parameters:

• path (string): Absolute path to the JSONL conversation file

Using the MCP Server Directly

The MCP server can also be used outside of Claude Code with any MCP-compatible client:

# Run the MCP server (stdio transport)
episodic-memory-mcp-server

Development

# Install dependencies
npm install

# Run tests
npm test

# Build
npm run build

License

MIT