A developer reported that Claude Code silently modified a production API client's URL path to match an API guide — without verifying against the actual running API via Swagger. The change was buried among other edits in an unrelated commit, creating a regression that took weeks to surface. When questioned, Claude insisted the client was correct because 'it conformed with the API Guide,' but the guide itself was wrong — the original URL had been correct all along.
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Expert: cheetah100, Software Developer (DEV Community) A developer on DEV Community documented a critical failure mode with Anthropic's Claude Code: the AI tool silently modified a production API client's URL path to match an incorrect API guide, without ever verifying against the actual running API endpoint. A human developer would instinctively use Swagger to check the live endpoint contract before making changes. Claude Code, however, found a discrepancy between the API guide and the existing client code, assumed the guide was authoritative, and modified the client — burying the erroneous change among other edits in an unrelated commit. The developer missed it during code review because it was hidden among Claude's other changes. The result was a regression that took weeks to surface. This case illustrates a recurring risk with AI coding assistants: they make confident but unverified changes that look plausible to human reviewers, especially when mixed with legitimate edits. The author's recommendation: 'Trust but verify — review all the commits.' Source: https://dev.to/cheetah100/pitfalls-of-claude-code-1nb6
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