Test Failure Analysis

Summary: A pre-existing flaky test unrelated to this PR failed on Python 3.10/ubuntu. This PR's single-line change (replacing a type: ignore comment) cannot cause this failure.

Root Cause: test_rate_limiting_blocks_rapid_requests is timing-sensitive. It sets max_requests_per_second=10.0 with burst_capacity=6, then makes 3 call_tool calls and expects the 4th to be rate-limited. The token bucket refills at 10 tokens/second — so as little as 0.1 seconds of elapsed time between async calls replenishes a token, allowing the 4th call to succeed instead of being blocked. On Python 3.10/ubuntu, async scheduling introduces enough real-world latency that the bucket refills before the limit is hit. Python 3.13 and Windows pass because their async scheduling is faster in this context.

Suggested Solution: The test in tests/server/middleware/test_rate_limiting.py:307 needs to be made timing-independent. Options:

1. Reduce the refill rate significantly — use max_requests_per_second=0.01 (or similarly tiny value) so tokens cannot realistically replenish between test calls.
2. Mock time.time() in the rate limiter so the test controls elapsed time explicitly, making it fully deterministic.
3. Consume all tokens upfront — use a burst capacity equal to exactly the number of calls made, with a refill rate so low it cannot recover within the test's duration.

The cleanest fix is option 1 or 2. Option 1 is a one-line change to the test fixture parameters.

FAILED tests/server/middleware/test_rate_limiting.py::TestRateLimitingMiddlewareIntegration::test_rate_limiting_blocks_rapid_requests
Failed: DID NOT RAISE <class 'fastmcp.exceptions.ToolError'>