One Missing 'Write a Script': How Skill Instructions Determine LLM Success or Failure
An AI assistant platform running Opus 4.6 hit stream_stall (90s timeout) twice consecutively when generating docx. Root cause: skill instructions lacked one sentence — 'Write a script' — causing the model to output JS code inline instead of writing a file and executing with node. Claude.ai's official SKILL.md has that sentence, and the model consistently takes the safe path.