RepoChatMCP

Search Claude Code and Codex chat history like source code.

RepoChatMCP is a zero-dependency MCP server and CLI for searching local Claude Code and Codex session files. It normalizes both providers into one message model, exposes search and read tools over MCP, and can optionally build a persisted repository knowledge index from your chat history.

No database. No background service. No telemetry. Just your local JSONL session files.

Why Use It

• Search Claude Code and Codex history from one MCP server

• Read sessions by message range or lines around a match

• Grep chats with AND, OR, and regex patterns

• Build repo knowledge summaries from prior chats

• Run locally with zero runtime dependencies

Related MCP server: engram-mcp

Package And Commands

• Published npm package: chat-search-mcp

• Installed CLI commands: chat-search and chat-search-mcp

• Runtime requirement: Node.js 22+

Install

Use the published npm package

Install it first:

npm install -g chat-search-mcp@latest

Then use it:

chat-search status --repo /path/to/repo
chat-search search "authentication" --repo /path/to/repo

Use the local repo checkout

git clone https://github.com/gzmagyari/RepoChatMCP.git
cd RepoChatMCP
npm install
node ./bin/chat-search.js status --repo .

Claude Code Setup

Project MCP from a local checkout

Use this when you cloned the repo and want Claude Code to run the local source directly:

{
  "mcpServers": {
    "chat-search": {
      "type": "stdio",
      "command": "node",
      "args": ["./bin/chat-search.js"]
    }
  }
}

Claude Code runs project MCPs from the repo directory, so ./bin/chat-search.js works and the current repo becomes the default target.

Use the published npm package

Install it first:

npm install -g chat-search-mcp@latest

macOS / Linux:

{
  "mcpServers": {
    "chat-search": {
      "type": "stdio",
      "command": "chat-search-mcp",
      "args": ["mcp"]
    }
  }
}

Windows:

{
  "mcpServers": {
    "chat-search": {
      "type": "stdio",
      "command": "cmd",
      "args": ["/c", "chat-search-mcp", "mcp"]
    }
  }
}

Codex Setup

Local checkout:

[mcp_servers.chat_search]
command = "node"
args = ["C:/path/to/RepoChatMCP/bin/chat-search.js"]

Published npm package on Windows:

[mcp_servers.chat_search]
command = "cmd"
args = ["/c", "chat-search-mcp", "mcp"]

CLI Quick Start

# MCP server
chat-search mcp --repo /path/to/repo

# Show discovered session counts
chat-search status --repo /path/to/repo

# Search across chats
chat-search search "jwt token" --repo /path/to/repo

If --repo is omitted, the current working directory is used.

MCP Tools

Example tool inputs

{ "query": "database pooling", "provider": "claude", "limit": 5 }

{ "pattern": "authentication&jwt" }

{ "sessionId": "8ac646f8-1bec-...", "startIndex": 0, "endIndex": 50 }

{ "force": true }

{ "provider": "codex", "limit": 10, "query": "database" }

{ "jobId": "knowledge-job-20260403-080000000-abc123def0" }

{ "batchId": "20260403-080000000-abc123def0", "kind": "knowledge", "offset": 0, "limit": 120 }

{ "query": "billing webhook", "kind": "content_summary", "limit": 5 }

Optional Knowledge Indexing

Knowledge indexing is disabled by default.

When disabled:

• chat.compaction_knowledge returns a live compaction snapshot file path

• chat.start_knowledge_index returns a configuration message instead of starting a job

• persisted knowledge can still be read later if .repochatmcp/knowledge/ already exists

When enabled:

• chat.start_knowledge_index creates an async indexing job instead of blocking the MCP call

• chat.get_knowledge_index_status reports discovery counts, chunk progress, files written, and failures

• chat.read_latest_knowledge and chat.read_knowledge_batch return actual paginated knowledge text, not just file paths

• chat.list_knowledge_files, chat.read_knowledge_file, and chat.search_knowledge let agents inspect persisted chunk files directly

• combined persisted batch artifacts are written under .repochatmcp/knowledge/combined/

• .repochatmcp/ is automatically added to the repo root .gitignore

Stored files:

• .repochatmcp/knowledge/manifest.json

• .repochatmcp/knowledge/jobs/*.json

• .repochatmcp/knowledge/runs/*.md

• .repochatmcp/knowledge/combined/*.md

Indexing rules:

• minimum 100 new or changed messages before indexing runs

• split only when transcript size exceeds CHAT_SEARCH_KNOWLEDGE_MAX_CHARS

• Codex chunk calls run sequentially

• HTTP chunk calls run with limited concurrency

• each chunk writes both a structured knowledge file and a plain content_summary file

• combined batch artifacts are persisted so agents can read one canonical file per batch

Backends

• off: disabled

• auto: prefer HTTP if API config is present, otherwise use Codex CLI

• http: OpenAI-compatible HTTP requests

• codex: Codex CLI over stdin

MCP env config

{
  "mcpServers": {
    "chat-search": {
      "type": "stdio",
      "command": "cmd",
      "args": ["/c", "chat-search-mcp", "mcp"],
      "env": {
        "CHAT_SEARCH_KNOWLEDGE_BACKEND": "http",
        "CHAT_SEARCH_KNOWLEDGE_BASE_URL": "https://openrouter.ai/api/v1",
        "CHAT_SEARCH_KNOWLEDGE_MODEL": "moonshotai/kimi-k2-0905@groq",
        "CHAT_SEARCH_KNOWLEDGE_API_KEY": "your-api-key",
        "CHAT_SEARCH_KNOWLEDGE_MAX_CHARS": "500000",
        "CHAT_SEARCH_KNOWLEDGE_HTTP_CONCURRENCY": "3"
      }
    }
  }
}

Supported env vars:

• CHAT_SEARCH_KNOWLEDGE_BACKEND=off|auto|http|codex

• CHAT_SEARCH_KNOWLEDGE_MODEL

• CHAT_SEARCH_KNOWLEDGE_BASE_URL

• CHAT_SEARCH_KNOWLEDGE_API_KEY

• CHAT_SEARCH_KNOWLEDGE_MAX_CHARS

• CHAT_SEARCH_KNOWLEDGE_TIMEOUT_MS

• CHAT_SEARCH_KNOWLEDGE_CODEX_BIN

• CHAT_SEARCH_KNOWLEDGE_HTTP_CONCURRENCY

OpenRouter provider pinning:

• set CHAT_SEARCH_KNOWLEDGE_BASE_URL=https://openrouter.ai/api/v1

• use CHAT_SEARCH_KNOWLEDGE_MODEL=model@provider, for example moonshotai/kimi-k2-0905@groq

• @provider is only valid for the OpenRouter HTTP backend

Unified Message Model

Both Claude Code and Codex are normalized to:

{
  provider: "claude" | "codex",
  sessionId: "uuid-or-session-id",
  index: 42,
  timestamp: "2026-03-25T10:11:12.000Z",
  type: "user" | "assistant" | "tool_call" | "tool_result" | "system" | "compaction",
  role: "user" | "assistant" | "system" | "developer",
  text: "message text"
}

Where Sessions Are Read From

Claude Code:

• ~/.claude/projects/<encoded-repo-path>/*.jsonl

Codex:

• ~/.codex/sessions/<year>/<month>/<day>/*.jsonl

• ~/.codex/archived_sessions/...

Configurable roots:

• CHAT_SEARCH_CLAUDE_ROOT

• CHAT_SEARCH_CODEX_SESSIONS

• CHAT_SEARCH_CODEX_ARCHIVED

Development

npm test

Current test suite: 79 tests covering discovery, normalization, search, MCP transport, async knowledge indexing jobs, direct persisted knowledge reads, and persisted knowledge indexing.

License

MIT