fix(deps): pin mcp SDK to <2.0.0 in MCP server examples - #46
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mcp 2.0.0 removed the legacy `Server` decorator API (`@app.list_resources()`,
`@app.list_tools()`, ...) that src/mssql_mcp_server/server.py is built on, so
an unconstrained install crashes at import time with:
AttributeError: 'Server' object has no attribute 'list_resources'
This bites `uvx --from git+...` launches in particular: they re-resolve
dependencies on every cold start and ignore uv.lock, so the server broke the
moment 2.0.0 hit PyPI. Consumers had to work around it with
`--with "mcp<2.0.0"` in their MCP client config.
- pyproject.toml / requirements.txt: mcp>=1.0.0 -> mcp>=1.0.0,<2.0.0
- uv.lock: regenerated (also picks up the stale project name
mssql-mcp-server -> microsoft-sql-server-mcp)
- README.md: document the pin and the condition for removing it
Verified: `uv pip compile pyproject.toml` now resolves mcp==1.29.0, and
`import mssql_mcp_server.server` succeeds. This is a stopgap - the real fix is
migrating the server to the 2.x API.
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Problem
mcp2.0.0 removed the legacyServerdecorator API this server is built on, so thepackage now fails at import time:
pyproject.tomldeclaredmcp>=1.0.0with no upper bound.uvx --from git+...launchesre-resolve dependencies on every cold start and ignore
uv.lock, so every client usingthat install path broke the moment 2.0.0 hit PyPI — no config or database change involved.
The only workaround was
--with "mcp<2.0.0"in each MCP client config.Change
pyproject.toml/requirements.txt:mcp>=1.0.0→mcp>=1.0.0,<2.0.0uv.lock: regenerated (also picks up the stale project namemssql-mcp-server→microsoft-sql-server-mcp)README.md: new "Dependency notes" section recording the pin and the condition for removing itVerification
uv pip compile pyproject.toml→mcp==1.29.0(this is the pathuvxtakes)import mssql_mcp_server.serversucceedsmcp1.2.0, so thepin is a no-op for
uv run. The 39 pre-existing failures intests/are untouched.Follow-up
This is a stopgap, not a migration. Removing the upper bound requires porting
server.pyto themcp2.x API.