claude-historian-mcp

A Model Context Protocol (MCP) server for searching your Claude Code conversation history. Find past solutions, track file changes, and learn from previous work.

install

Requirements:

Claude Code

From shell:

claude mcp add claude-historian-mcp -- npx claude-historian-mcp

From inside Claude (restart required):

Add this to our global mcp config: npx claude-historian-mcp

Install this mcp: https://github.com/Vvkmnn/claude-historian-mcp

From any manually configurable mcp.json: (Cursor, Windsurf, etc.)

{
  "mcpServers": {
    "claude-historian-mcp": {
      "command": "npx",
      "args": ["claude-historian-mcp"],
      "env": {}
    }
  }
}

That's it; there is no npm install required as there are no external dependencies or local databases, only search algorithms.

However, in the unlikely event that you pull the wrong package / npx registry is out of date, you can force resolution issues in certain environments with:

npm install -g claude-historian-mcp

📦 renamed: This project was renamed from claude-historian to claude-historian-mcp. Existing users should update your install command and MCP config args to claude-historian-mcp.

features

MCP server that gives Claude access to your conversation history. Fast search with smart prioritization.

Runs locally (with cool shades [⌐■_■]):

search_conversations

Search your conversation history for past solutions, discussions, and context.

[⌐■_■] search_conversations query=<query>
  > "How did we fix that Redis connection pooling nightmare?"
  > "Docker container keeps crashing on Kubernetes deployment"
  > "React infinite re-render loop - useEffect dependency hell"

[⌐■_■] "docker auth" | 2 results

{
  "results": [{
    "type": "assistant",
    "ts": "2h ago",
    "content": "Fixed Docker auth by updating registry credentials...",
    "project": "my-app",
    "score": 15,
    "ctx": { "filesReferenced": ["docker-compose.yml"], "toolsUsed": ["Edit", "Bash"] }
  }]
}

find_file_context

Track modifications, edits, and discussions about specific files across sessions.

[⌐□_□] find_file_context filepath=<filepath>
  > "package.json changes that broke everything last month"
  > "When we accidentally committed .env to main branch"
  > "Authentication service refactor - before/after comparison"

[⌐□_□] "package.json" | 5 operations

{
  "filepath": "package.json",
  "operations": [{
    "type": "edit",
    "ts": "1d ago",
    "changes": ["added vitest dependency", "updated build script"],
    "ctx": { "filesReferenced": ["package.json", "vitest.config.ts"] }
  }]
}

get_error_solutions

Find how you've resolved similar errors before, with code fixes and patterns.

[⌐×_×] get_error_solutions error_pattern=<error>
  > "MODULE_NOT_FOUND - the classic npm/yarn version mismatch"
  > "CORS preflight failing - but only on production Fridays?"
  > "Database deadlock during Black Friday traffic spike"

[⌐×_×] "ENOENT no such file" | 2 solutions

{
  "solutions": [{
    "pattern": "ENOENT: no such file or directory",
    "frequency": 3,
    "fixes": [{ "content": "Created missing directory", "code": ["mkdir -p ./dist"] }]
  }]
}

find_similar_queries

Discover related questions you've asked before and their answers.

[⌐◆_◆] find_similar_queries query=<query>
  > "Database queries slower than my morning coffee brewing"
  > "How to implement error boundaries without losing sanity"
  > "State management: Redux vs Zustand vs just useState"

[⌐◆_◆] "typescript error handling" | 3 similar

{
  "similar": [{
    "query": "how to handle async errors in typescript",
    "similarity": 0.72,
    "ts": "3d ago",
    "project": "api-server"
  }]
}

list_recent_sessions

Browse your recent Claude sessions with project context and accomplishments.

[⌐○_○] list_recent_sessions
  > "Tuesday debugging marathon: 9pm-3am flaky test hunt"
  > "Performance optimization sprint - reduced bundle 40%"
  > "The great TypeScript migration of 2024"

[⌐○_○] all | 3 sessions

{
  "sessions": [{
    "id": "68d5323b",
    "ts": "2h ago",
    "duration": 45,
    "messages": 128,
    "project": "my-app",
    "tools": ["Edit", "Bash", "Read"],
    "accomplishments": ["fixed auth bug", "added unit tests"]
  }]
}

find_tool_patterns

Learn from your successful tool usage workflows and common sequences.

[⌐⎚_⎚] find_tool_patterns tool_name=<tool>
  > "Read → Edit → Bash combo for rapid prototyping"
  > "When I use Grep vs Task for different searches"
  > "Git operations during feature branch management"

[⌐⎚_⎚] "Edit" | 3 patterns

{
  "tool": "Edit",
  "patterns": [{
    "name": "Read → Edit → Bash",
    "uses": 7,
    "workflow": "Read → Edit → Bash",
    "practice": "Read file, edit, then run tests (7x successful)"
  }]
}

search_plans

Search Claude Code plan files for past implementation approaches, decisions, and patterns.

[⌐▣_▣] search_plans query=<query>
  > "How did we architect the authentication system?"
  > "Database migration strategy from last refactor"
  > "API versioning approach we decided on"

[⌐▣_▣] "auth implementation" | 2 plans

{
  "plans": [{
    "file": "implement-oauth.md",
    "ts": "3d ago",
    "project": "my-app",
    "summary": "OAuth2 implementation with refresh tokens...",
    "decisions": ["chose PKCE flow", "JWT for access tokens"]
  }]
}

extract_compact_summary

Get a concise summary of what was accomplished in a specific session.

[⌐◉_◉] extract_compact_summary session_id=<id>
  > "What did we accomplish in last session?"
  > "Summarize the authentication refactor work"
  > "Key decisions from yesterday's debugging"

[⌐◉_◉] extracting summary from my-app (68d5323b)

{
  "session": {
    "id": "68d5323b",
    "ts": "2h ago",
    "duration": 45,
    "messages": 128,
    "project": "my-app",
    "tools": ["Edit", "Bash", "Read"],
    "files": ["src/auth.ts", "package.json"],
    "accomplishments": ["fixed auth bug", "added unit tests"],
    "decisions": ["chose JWT over sessions"]
  }
}

methodology

How claude-historian works:

"docker auth" query
      |
      ├─> Parallel Processing (search.ts:157): 15 projects × 10 files concurrently
      |   • Promise.allSettled for 6x speed improvement
      |   • Early termination when sufficient results found
      |   • Enhanced file coverage with comprehensive patterns
      |
      ├─> Enhanced Classification (search.ts:582): implementation → boost tool workflows
      |   • Workflow detection for tool sequences (Edit → Read → Bash)
      |   • Semantic boundary preservation (never truncate mid-function)
      |   • Claude-optimized formatting with rich metadata
      |
      ├─> Smart Ranking (search.ts:637):
      |   • "Edit workflow (7x successful)" (2h ago) *****
      |   • "Docker auth with context paths" (yesterday) ****
      |   • "Container debugging patterns" (last week) ***
      |
      └─> Return Claude Code optimized results

Core optimizations:

• parallel processing: Promise.allSettled for 6x speed improvement across projects and files
• workflow detection: Captures tool sequences like "Edit → Read → Bash" patterns
• enhanced file matching: Comprehensive path variations with case-insensitive matching
• intelligent deduplication: Content-based deduplication preserving highest-scoring results
• intelligent truncation: Never truncates mid-function or mid-error
• Claude-optimized formatting: Rich metadata with technical content prioritization

Search strategies:

• JSON streaming parser (parseJsonlFile): Reads Claude Code conversation files on-demand without full deserialization
• LRU caching (messageCache): In-memory cache with intelligent eviction for frequently accessed conversations
• TF-IDF inspired scoring (calculateRelevanceScore): Term frequency scoring with document frequency weighting for relevance
• Query classification (classifyQueryType): Naive Bayes-style classification (error/implementation/analysis/general) with adaptive limits
• Edit distance (calculateQuerySimilarity): Fuzzy matching for technical terms and typo tolerance
• Exponential time decay (getTimeRangeFilter): Recent messages weighted higher with configurable half-life
• Parallel file processing (getErrorSolutions): Concurrent project scanning with early termination for 0.8s response times
• Workflow pattern recognition (getToolPatterns): Detects tool usage sequences and related workflows for learning
• Enhanced file context (findFileContext): Multi-project search with comprehensive path matching
• Content-aware truncation (smartTruncation): Intelligent content boundaries over arbitrary character limits
• Technical content prioritization (BeautifulFormatter): Code blocks, errors, and file paths get full preservation
• Query similarity clustering (findSimilarQueries): Semantic expansion and pattern grouping for related questions

File access:

• Reads from: ~/.claude/conversations/
• Zero persistent storage or indexing
• Never leaves your machine

performance

See PERF.md for benchmarks, optimization history, and quality scores.

Current (v1.0.4): 4.7/5 average score across 8 tools. Latest: fixed word matching bug eliminating false positives (e.g., "react" vs "ReAct"), +1.0 point search relevance improvement.

development

git clone https://github.com/vvkmnn/claude-historian-mcp && cd claude-historian
npm install && npm run build
npm test

Package requirements:

• Node.js: >=20.0.0 (ES modules support)
• npm: >=10.0.0 (package-lock v3)
• Runtime: Only @modelcontextprotocol/sdk dependency
• Zero external dependencies for production deployment
• Optimized: 50% token reduction with parallel processing

Development workflow:

npm run build          # TypeScript compilation with executable permissions
npm run dev            # Watch mode with tsc --watch
npm run start          # Run the MCP server directly
npm run lint           # ESLint code quality checks
npm run lint:fix       # Auto-fix linting issues
npm run format         # Prettier formatting (src/)
npm run format:check   # Check formatting without changes
npm run type-check     # TypeScript validation without emit
npm run test           # Run help command + type check
npm run prepublishOnly # Pre-publish validation (build + lint + format:check)

Git hooks (via Husky):

• pre-commit: Auto-formats staged .ts files with Prettier and ESLint
• pre-push: Runs full validation (format, lint, type-check, build) before push

Contributing:

• Please fork the repository and create feature branches
• Test with large conversation histories before submitting PRs
• Follow TypeScript strict mode and MCP protocol standards

Learn from examples:

• Official MCP servers for reference implementations
• TypeScript SDK for best practices
• Creating Node.js modules - NPM package development guide

desktop

Note: Claude Desktop stores conversations server-side, not locally. The local LevelDB files (~/Library/Application Support/Claude/) contain only session tokens, UI preferences, and Intercom state - not conversation content. Claude Desktop support is also blocked by LevelDB locks and Electron sandboxing.

This means local history search for Claude Desktop is not currently possible. This project focuses on Claude Code, which stores full conversation history locally in ~/.claude/projects/.

You may get some Claude Desktop from Claude Code, but only when the Claude app is closed. Furthermore A DXT package and build is available for future compatibility; further investigations are ongoing. Feel free to test with it.

alternatives

claude-mem - Plugin with SQLite database and always-on context loading.

Real-world testing (over 270+ sessions):

• 95% of sessions never query history (Result: 98% token savings):
  • claude-mem: 5-8k tokens × 95 wasted = 475k wasted tokens
  • claude-historian-mcp: 0 × 95 + (500-2k × 5 queries) = 2.5-10k tokens
• Plugin + external database has more overhead on every session / machine start:
  • claude-historian-mcp: zero startup overhead, instant first response
  • claude-mem: processes full context before every first response (cached tokens are cheaper to bill, not faster to process)
  • claude-mem only has savings if querying history in >50% of sessions (very uncommon)
• Some issues are still being debugged, and can break a session:
  • Creates stub session files that break --continue command
  • Worker daemon version conflicts cause connection failures
  • Security hooks block valid documentation edits

license

MIT

Claude Fauchet (1744-1793), French Historian