Fix FastMCP compatibility issue #77
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The excel-mcp-server was using outdated FastMCP API parameters (version, description, dependencies, env_vars) that are no longer supported in the current FastMCP version. Updated the initialization to use only the supported parameters (name and instructions) to resolve the TypeError. Also added explicit dependency on fastmcp>=2.0.0,<3.0.0 to ensure compatibility with FastMCP 2.x API and prevent future breaking changes from major version updates. This fixes the "TypeError: FastMCP.__init__() got an unexpected keyword argument 'version'" error when running excel-mcp-server. Fixes haris-musa#76
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Summary
Users updating their environments (e.g., running
pip install --upgradeor reinstalling) suddenly find excel-mcp-server broken with a TypeError. This PR fixes the FastMCP 2.x compatibility issue and adds version constraints to prevent future breaking changes.Root Cause Analysis
The excel-mcp-server uses FastMCP, a Python framework for building MCP (Model Context Protocol) servers. The excel-mcp-server was configured with an unbounded version constraint for its dependencies. The
pyproject.tomlonly specifiedmcp[cli]>=1.10.1without any upper bound, which allowed any newer version to be installed, including versions with breaking API changes.When FastMCP released version 2.0 (compare v1.0...v2.0.0), it introduced breaking changes to the API. The FastMCP constructor was changed in
src/fastmcp/server/server.py:v1.0: The constructor accepted various parameters through
**settingsv2.0: The constructor now explicitly requires
nameandinstructionsparameters, while the old parameters (version,description,dependencies,env_vars) are no longer supportedThis caused the following error for users:
Solution
This PR implements a two-part fix:
1. Code Changes
Updated the FastMCP initialization to use only the currently supported parameters:
version,dependencies,env_varsdescriptionparameter toinstructions2. Dependency Constraints
Added explicit version constraints to prevent future breaking changes:
fastmcp>=2.0.0,<3.0.0to dependenciesTesting
Tested locally with FastMCP 2.10.6 and confirmed the server starts successfully without errors.
Fixes #76