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 ## Tools
 
+- [check-proxy-tax](https://github.com/600me/check-proxy-tax) - CLI that samples a URL concurrently and reports usable-response rate, latency, and effective cost per 1,000 usable requests.
 - [CrossHair](https://github.com/pschanely/CrossHair) - An analysis tool for Python that blurs the line between testing and type systems.
 - [csv-quality-gate](https://github.com/hermes-labs-ai/csv-quality-gate) - A Python CLI that checks CSV test datasets and pipeline inputs for missing columns, empty cells, and duplicate rows, with configurable rules and CI exit codes.
 - [ghostwriter](https://hypothesis.readthedocs.io/en/latest/ghostwriter.html) - Writing tests with Hypothesis frees you from the tedium of deciding on and writing out specific inputs to test.