Hooktheory MCP Server
Click on "Deploy Server".
Wait a few minutes for the server to deploy. Once ready, it will show a "Started" state.
In the chat, type
@followed by the MCP server name and your instructions, e.g., "@Hooktheory MCP Server find songs with the chord progression I-V-vi-IV in C major"
That's it! The server will respond to your query, and you can continue using it as needed.
Here is a step-by-step guide with screenshots.
Hooktheory MCP Server
A Model Context Protocol (MCP) server that enables AI agents to interact with the Hooktheory API for chord progression generation, song analysis, and music theory data retrieval.
Quick Start
Get up and running in 3 simple steps:
Set up authentication using your Hooktheory account credentials:
export HOOKTHEORY_USERNAME="your-username" export HOOKTHEORY_PASSWORD="your-password"Install and run:
uvx hooktheory-mcpTry these examples with your AI assistant:
"Find songs with the chord progression I-V-vi-IV"
"Analyze the song 'Wonderwall' by Oasis"
"Show me popular chord progressions in C major"
"Find songs similar to 'Let It Be' by The Beatles"
That's it! Your AI can now access music theory data and chord progressions.
Related MCP server: Scribbletune MCP Server
Common Usage Examples
Search for Songs by Chord Progression
Find songs using the progression 1,5,6,4 in the key of C majorAnalyze Any Song
What are the chords in "Someone Like You" by Adele?Discover Popular Progressions
What are the most common chord progressions in pop music?Find Similar Songs
Find songs that have similar chord progressions to "Hotel California"Features
The server provides the following tools for music analysis and generation:
Chord Progression Search: Find songs with specific chord progressions
Song Analysis: Analyze specific songs to get chord progressions and key information
Popular Progressions: Discover the most popular chord progressions
Similar Songs: Find songs with similar chord progressions
Progression Generation: Generate chord progressions based on music theory patterns
Installation
Prerequisites
Python 3.11 or higher
A Hooktheory account (Sign up at https://www.hooktheory.com)
Setup
Install with uvx (recommended):
uvx hooktheory-mcpOr install from source:
git clone <repository-url> cd hooktheory-mcp uv syncSet up authentication:
export HOOKTHEORY_USERNAME="your-username" export HOOKTHEORY_PASSWORD="your-password"Or create a
.envfile:HOOKTHEORY_USERNAME=your-username HOOKTHEORY_PASSWORD=your-passwordTest the installation:
uvx hooktheory-mcp --help # Or if installed from source: uv run hooktheory-mcp --help
Usage
Command Line
The server can be run in different modes:
Standard MCP mode (stdio transport):
uvx hooktheory-mcp
# Or from source: uv run hooktheory-mcpStreamable HTTP mode for web integration:
uvx hooktheory-mcp --transport streamable-http
# Or from source: uv run hooktheory-mcp --transport streamable-httpServer-Sent Events (SSE) mode:
uvx hooktheory-mcp --transport sse
# Or from source: uv run hooktheory-mcp --transport sseMCP Client Configuration
For Claude Desktop, add this to your configuration:
{
"mcpServers": {
"hooktheory": {
"command": "uvx",
"args": ["hooktheory-mcp"],
"env": {
"HOOKTHEORY_USERNAME": "your-username",
"HOOKTHEORY_PASSWORD": "your-password"
}
}
}
}Alternative for development/local install:
{
"mcpServers": {
"hooktheory": {
"command": "uv",
"args": ["run", "hooktheory-mcp"],
"cwd": "/path/to/hooktheory-mcp",
"env": {
"HOOKTHEORY_USERNAME": "your-username",
"HOOKTHEORY_PASSWORD": "your-password"
}
}
}
}Available Tools
1. get_chord_progressions
Search for songs with specific chord progressions.
Parameters:
cp(required): Chord progression in Roman numeral notation (e.g., "1,5,6,4")key(optional): Musical key (e.g., "C", "Am")mode(optional): Scale mode ("major", "minor")artist(optional): Filter by artist namesong(optional): Filter by song title
Example:
Find songs with the progression I-V-vi-IV in the key of C major2. analyze_song
Analyze a specific song to get its chord progression and music theory data.
Parameters:
artist(required): Artist namesong(required): Song title
Example:
Analyze "Wonderwall" by Oasis3. get_popular_progressions
Get the most popular chord progressions from the database.
Parameters:
key(optional): Filter by musical keymode(optional): Filter by scale modelimit(optional): Max results (default: 20)
Example:
Show me the most popular chord progressions in C major4. find_similar_songs
Find songs with similar chord progressions to a reference song.
Parameters:
artist(required): Reference artist namesong(required): Reference song titlesimilarity_threshold(optional): Similarity score 0.0-1.0 (default: 0.7)
Example:
Find songs similar to "Let It Be" by The Beatles5. generate_progression
Generate chord progressions based on music theory patterns.
Parameters:
key(optional): Starting key (default: "C")mode(optional): Scale mode (default: "major")length(optional): Number of chords (default: 4)style(optional): Musical style hint ("pop", "rock", "jazz")
Example:
Generate a 4-chord pop progression in A minorAPI Integration
The server integrates with the Hooktheory API using OAuth 2.0 authentication:
Base URL:
https://www.hooktheory.com/apiAuthentication: OAuth 2.0 with username/password → Bearer token
Rate Limiting: 1.5 requests/second with exponential backoff
Token Management: Automatic token caching and refresh (24-hour expiry)
Error Recovery: Automatic retry with backoff on rate limits and auth failures
Authentication Flow
Server exchanges username/password for Bearer token via
POST /users/authToken is cached and automatically refreshed when expired
All API requests use Bearer token authentication
Rate limiting prevents exceeding API limits with intelligent backoff
Development
Project Structure
hooktheory-mcp/
├── src/hooktheory_mcp/
│ └── __init__.py # Main MCP server implementation
├── pyproject.toml # Project configuration
├── uv.lock # Dependency lock file
└── README.md # This fileAdding New Tools
To add new tools, edit src/hooktheory_mcp/__init__.py and add new functions decorated with @mcp.tool():
@mcp.tool()
async def your_new_tool(param1: str, param2: Optional[int] = None) -> str:
"""
Description of your tool.
Args:
param1: Description of parameter
param2: Optional parameter description
Returns:
Description of return value
"""
# Implementation here
return resultTesting
# Run basic connectivity test
uv run python -c "
import asyncio
from hooktheory_mcp import hooktheory_client
asyncio.run(hooktheory_client._make_request('test'))
"Troubleshooting
Common Issues
Authentication Credentials Not Set
Error: HOOKTHEORY_USERNAME and HOOKTHEORY_PASSWORD environment variables are requiredSolution: Set both
HOOKTHEORY_USERNAMEandHOOKTHEORY_PASSWORDenvironment variablesHTTP 401 Unauthorized
HTTP error calling https://www.hooktheory.com/api/trends/...: 401Solution: Verify your username and password are correct. The server will automatically retry authentication.
Rate Limited (HTTP 429)
Rate limited. Waiting X seconds before retrySolution: This is normal - the server automatically handles rate limiting with exponential backoff
Connection Errors
HTTP error calling https://www.hooktheory.com/api/trends/...: ConnectErrorSolution: Check internet connection and Hooktheory API status
Debug Mode
Enable debug logging:
export PYTHONPATH=src
python -c "
import logging
logging.basicConfig(level=logging.DEBUG)
from hooktheory_mcp import main
main()
"Contributing
Fork the repository
Create a feature branch
Make your changes
Add tests if applicable
Submit a pull request
License
This project is licensed under the MIT License - see the LICENSE file for details.
Links
Available Tools
2 toolsget_chord_transitionsA
Get chord statistics and transition probabilities from Hooktheory database.
Args:
cp: Optional chord progression to get transitions from (e.g., "4" for chords after IV, "4,1" for chords after IV-I)
If not provided, returns overall chord frequency statistics
key: Musical key filter (e.g., "C", "Am")
mode: Scale mode filter ("major" or "minor")
Returns:
JSON string containing chord nodes with chord_ID, chord_HTML (Roman numeral), probability, and child_path
- Without cp: Shows overall chord frequencies (I=18.9%, IV=17.2%, etc.)
- With cp: Shows what chords follow the progression (e.g., after IV: I=32.4%, V=28.9%)
Inputs: cp, key, mode. Returns: result
get_songs_by_progressionA
Get songs that contain a specific chord progression from Hooktheory.
Args:
cp: Chord progression using comma-separated chord IDs (e.g., "1,5,6,4" for I-V-vi-IV, "4,1" for IV-I)
page: Page number for pagination (default: 1, each page contains ~20 results)
key: Musical key filter (e.g., "C", "Am")
mode: Scale mode filter (e.g., "major", "minor")
Returns:
JSON string containing array of songs with artist, song, section, and URL
Inputs: cp (required), page, key, mode. Returns: result
Tool Schema Changelog
Recent tool additions, removals, and schema changes observed during successful MCP inspections.
Loading tool schema changelog…
TDQS
Scored across 2 tools
The two tools have clearly distinct purposes: get_chord_transitions retrieves chord statistics and transition probabilities, while get_songs_by_progression finds songs containing specific chord progressions. There is no overlap in functionality, making it easy for an agent to select the correct tool based on whether it needs analytical data or song references.
Both tool names follow a consistent verb_noun pattern with get_ as the verb prefix and descriptive nouns (chord_transitions, songs_by_progression). The naming is predictable and readable, adhering to snake_case throughout without any deviations or mixed conventions.
With only 2 tools, the server feels under-scoped for a music theory domain, as it lacks essential operations like searching for chords, analyzing melodies, or accessing other Hooktheory features. This minimal set may force agents to work around gaps, limiting the server's utility beyond basic queries.
The tool surface is severely incomplete for a Hooktheory server, missing core functionalities such as chord lookup, melody analysis, or accessing user data. While the existing tools cover chord transitions and song searches, they do not provide a full CRUD/lifecycle or comprehensive coverage of the music theory domain, leading to potential agent failures in broader tasks.
Maintenance
Related MCP Connectors
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Deterministic music theory for agents: analyze, voice, reharmonize, conduct — computed, not guessed
Access Pollinations models and API capabilities through agent tools.
Autonomous music production for AI agents with MIDI generation, QC and provenance.
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