Claude Skills Silently Override Instructions: Undocumented Pitfalls Exposed
A Reddit user digging into Claude Skills found multiple silent behaviors that override explicit instructions, with no documentation in skill-creator. Here's what they uncovered.
Key Pitfalls in Claude Skills
ask_user_input_v0hard limits: The tool enforces a maximum of 3 questions and 4 options per question. If a skill requests more, Claude silently compacts them. No error is raised.- File write inconsistency: On Code/Desktop,
Writesilently overwrites existing files. On Claude.ai,create_filerefuses to overwrite. Same instruction, opposite behavior. - Relative paths in
references/are broken: The officially recommendedreferences/pattern doesn't resolve relative paths from the skill's directory on any platform. - Silent fallback for missing tools: If a skill references a tool that doesn't exist on the running platform, Claude falls back to prose without any error or warning.
Practical Fixes
The author's fix: update skills to ask multiple rounds when more input is needed, bypassing the ask_user_input_v0 limits. For file operations, always use Write on Code/Desktop and create_file with platform checks on Claude.ai. Avoid relative paths in references/; use absolute paths or inline content instead.
Community-Shared Repo
Findings are being collected in a GitHub repository: github.com/livlign/claude-skills-pitfalls. Contributions welcome.
Who Should Care
Anyone building or maintaining Claude Skills, especially those relying on user input flows or cross-platform behaviors.
📖 Read the full source: r/ClaudeAI
👀 See Also
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