Skip to main content

Token-optimized semantic code search MCP server for AI coding assistants

Project description

WashedMCP -- Token-Optimized Semantic Code Search

An MCP (Model Context Protocol) server that provides token-efficient semantic code search with automatic context expansion for AI coding assistants.

⚡ Quickest Start (Copy & Paste)

# Install
pip install washedmcp

# Add to Claude Code config (~/.claude.json)
cat >> ~/.claude.json << 'EOF'
{
  "mcpServers": {
    "washedmcp": {
      "command": "python3",
      "args": ["-m", "washedmcp.mcp_server"]
    }
  }
}
EOF

# Restart Claude Code, then say:
# "Index this codebase and search for authentication"

Or use the setup script:

curl -fsSL https://raw.githubusercontent.com/clarsbyte/washedmcp/main/setup-claude.sh | bash

The Problem

When AI assistants search codebases, they get isolated results without context:

  • Need multiple searches to understand call chains
  • Waste tokens on redundant lookups
  • Lose context between tool calls

The Solution

WashedMCP returns comprehensive context in a single search:

Query: "user validation logic"

FOUND: validate() in src/auth.js:42 (82% match)

CODE:
  function validate(data) {
    if (!checkEmail(data.email)) return false;
    if (!checkPassword(data.password)) return false;
    return sanitize(data);
  }

CALLS: checkEmail, checkPassword, sanitize
CALLED BY: processUser, createUser
SAME FILE: [sanitize, normalizeInput, validateSchema]

One search -> full context -> immediate action.

Features

  • Semantic Search -- Find code by meaning, not just keywords
  • Context Expansion -- Automatically include callers/callees
  • Code Graph -- Track function relationships (calls, called_by)
  • TOON Format -- Token-Optimized Object Notation (~30-40% fewer tokens than JSON)
  • Multi-Language -- Python, JavaScript, TypeScript, JSX, TSX

Requirements

  • Python 3.10-3.13 (Python 3.14+ is not yet supported due to onnxruntime compatibility)
  • ~500MB disk space for model and dependencies

Installation

One-liner (recommended)

curl -fsSL https://raw.githubusercontent.com/clarsbyte/washedmcp/main/install.sh | bash

Restart Claude Code. Done.

Using pip

pip install washedmcp

Using pipx (recommended for macOS)

pipx installs packages in isolated environments, avoiding conflicts with system Python:

# Install pipx if you don't have it
brew install pipx
pipx ensurepath

# Install washedmcp
pipx install washedmcp

Manual Installation (Virtual Environment)

If you encounter issues with pip or pipx, use a virtual environment:

# Create a virtual environment
python3 -m venv ~/.washedmcp-venv

# Activate it
source ~/.washedmcp-venv/bin/activate

# Install washedmcp
pip install washedmcp

# The washedmcp command is now available when the venv is activated

For permanent access, add an alias to your shell config (~/.bashrc or ~/.zshrc):

alias washedmcp="~/.washedmcp-venv/bin/washedmcp"

Configure Claude Code

Add to ~/.claude.json:

{
  "mcpServers": {
    "washedmcp": {
      "command": "washedmcp"
    }
  }
}

If using a virtual environment:

{
  "mcpServers": {
    "washedmcp": {
      "command": "/Users/YOUR_USERNAME/.washedmcp-venv/bin/washedmcp"
    }
  }
}

Restart Claude Code after configuration.

Usage

After install, you get 3 tools in Claude Code:

# Index your project first
index_codebase("/path/to/your/project")

# Search semantically
search_code("authentication logic")

# Check status
get_index_status()

MCP Tools

Tool Description
index_codebase Index a codebase for semantic search
search_code Search with context expansion (depth parameter)
get_index_status Check if codebase is indexed
get_token_savings Show cumulative token savings from TOON vs JSON

How It Works

+--------------------------------------------------+
|               CONTEXT EXPANSION                   |
+--------------------------------------------------+
|                                                   |
|  Query: "validation failing"                      |
|              |                                    |
|              v                                    |
|  +-----------------------------+                  |
|  |  1. Semantic Search         |                  |
|  |     (embeddings + cosine)   |                  |
|  +-----------------------------+                  |
|              |                                    |
|              v                                    |
|  +-----------------------------+                  |
|  |  2. Context Expansion       |                  |
|  |     - CALLS: [...]          |                  |
|  |     - CALLED BY: [...]      |                  |
|  |     - SAME FILE: [...]      |                  |
|  +-----------------------------+                  |
|              |                                    |
|              v                                    |
|  +-----------------------------+                  |
|  |  3. TOON Output             |                  |
|  |     (token-efficient)       |                  |
|  +-----------------------------+                  |
|                                                   |
+--------------------------------------------------+

Tech Stack

  • Parsing: tree-sitter (multi-language AST extraction)
  • Embeddings: sentence-transformers/all-MiniLM-L6-v2
  • Vector DB: ChromaDB (persistent, cosine similarity)
  • MCP: fastmcp
  • Summarization: Google Generative AI (optional)

Project Structure

washedmcp/
+-- washedmcp/            # Python package
|   +-- parser.py         # AST parsing + call extraction
|   +-- embedder.py       # Embedding generation
|   +-- database.py       # ChromaDB + relationships
|   +-- indexer.py        # Indexing orchestration
|   +-- searcher.py       # Search + context expansion
|   +-- toon_formatter.py # TOON output format
|   +-- mcp_server.py     # MCP server entry point
+-- install.sh            # One-line installer
+-- pyproject.toml        # Package config
+-- requirements.txt      # Dependencies

Context Expansion Depth

Control how many hops of relationships to include:

  • depth=1 (default): Direct callers + callees
  • depth=2: Include callers of callers (for debugging chains)
# MCP tool call
search_code(query="validation", depth=2)

WashedMCP also includes a recommendation and auto installation MCP pipeline built with LeanMCP.

It uses tool call interception with hooks and tool call memory to:

  • Recommend MCP tools based on repeated assistant behavior
  • Auto install and configure MCP tools to remove setup friction
  • Reduce repeated lookups by remembering previous tool usage patterns

This turns the MCP tool layer into something that improves over time during longer coding sessions.

Troubleshooting

Python Version Issues

Error: "No matching distribution found for onnxruntime"

This happens when using Python 3.14+, which doesn't have onnxruntime wheels yet.

Solution: Use Python 3.10-3.13

# macOS (Homebrew)
brew install python@3.12
/opt/homebrew/bin/python3.12 -m pip install washedmcp

# Or use pyenv
pyenv install 3.12
pyenv global 3.12
pip install washedmcp

onnxruntime Installation Fails

Error: "Could not build wheels for onnxruntime"

onnxruntime (used by sentence-transformers) requires specific Python versions.

Solutions:

  1. Use Python 3.10-3.13 (recommended)
  2. Install pre-built wheels:
    pip install --only-binary :all: onnxruntime
    pip install washedmcp
    

ChromaDB Issues

Error: "sqlite3.OperationalError" or ChromaDB errors

ChromaDB requires SQLite 3.35+. Some older systems have outdated SQLite.

Solutions:

  1. macOS: Update with Homebrew

    brew install sqlite3
    
  2. Linux: Use pysqlite3-binary

    pip install pysqlite3-binary
    

    Then add to your shell profile:

    export LD_PRELOAD=/usr/lib/x86_64-linux-gnu/libsqlite3.so.0
    

"externally-managed-environment" Error (macOS/Linux)

Modern Python installations prevent pip from modifying system packages.

Solution: Use pipx

# macOS
brew install pipx
pipx ensurepath
pipx install washedmcp

# Linux
pip install --user pipx
pipx ensurepath
pipx install washedmcp

Command Not Found After Installation

If washedmcp isn't found after pip install:

  1. Check if it's in your PATH:

    python3 -m site --user-base
    # Add the bin subdirectory to PATH
    export PATH="$HOME/.local/bin:$PATH"
    
  2. Add to your shell config (~/.bashrc or ~/.zshrc):

    export PATH="$HOME/.local/bin:$PATH"
    
  3. Or use the full path in Claude config:

    {
      "mcpServers": {
        "washedmcp": {
          "command": "python3",
          "args": ["-m", "washedmcp.mcp_server"]
        }
      }
    }
    

First Run Is Slow

On first use, washedmcp downloads the embedding model (~100MB). This is a one-time operation. Subsequent runs will be fast.

Index Not Found

If search returns "codebase not indexed":

  1. Run index_codebase("/path/to/project") first
  2. The index is stored in <project>/.washedmcp/
  3. Re-index after major code changes

License

MIT

Project details


Download files

Download the file for your platform. If you're not sure which to choose, learn more about installing packages.

Source Distribution

washedmcp-0.2.1.tar.gz (76.8 kB view details)

Uploaded Source

Built Distribution

If you're not sure about the file name format, learn more about wheel file names.

washedmcp-0.2.1-py3-none-any.whl (68.4 kB view details)

Uploaded Python 3

File details

Details for the file washedmcp-0.2.1.tar.gz.

File metadata

  • Download URL: washedmcp-0.2.1.tar.gz
  • Upload date:
  • Size: 76.8 kB
  • Tags: Source
  • Uploaded using Trusted Publishing? No
  • Uploaded via: twine/6.2.0 CPython/3.10.0

File hashes

Hashes for washedmcp-0.2.1.tar.gz
Algorithm Hash digest
SHA256 f9cf2fe7ae080ba4316784eaa3eeffbc19ddfe7c7f851f002a5c39cc432ed23e
MD5 205f18dcf43615397e4dfd12be19826a
BLAKE2b-256 81ed1cc5f9aa388745f592c2d9e3c140c18a724c39345cde352984c82b31c251

See more details on using hashes here.

File details

Details for the file washedmcp-0.2.1-py3-none-any.whl.

File metadata

  • Download URL: washedmcp-0.2.1-py3-none-any.whl
  • Upload date:
  • Size: 68.4 kB
  • Tags: Python 3
  • Uploaded using Trusted Publishing? No
  • Uploaded via: twine/6.2.0 CPython/3.10.0

File hashes

Hashes for washedmcp-0.2.1-py3-none-any.whl
Algorithm Hash digest
SHA256 327924c4ab972dfafcacd1204b0ad1d3aee5a84200666d697de5bcb7246d74ae
MD5 5c230a1add5dc35717eab3e8d2f98fb2
BLAKE2b-256 34c48c8d98e32dbbb3a39e58e19f887c59efa53e93414146924f0d75ee1a43bf

See more details on using hashes here.

Supported by

AWS Cloud computing and Security Sponsor Datadog Monitoring Depot Continuous Integration Fastly CDN Google Download Analytics Pingdom Monitoring Sentry Error logging StatusPage Status page