Agent Skills: usage-insights

Generate a usage insights report analyzing coding assistant session history. Parses session JSONL logs, extracts metadata (tools used, languages, git activity, friction points), and produces a structured markdown analysis with actionable suggestions. Works with any assistant that stores sessions as JSONL. Use when the user says "/usage-insights", "analyze my sessions", "usage report", "how am I using this", "session insights", or asks to review their coding assistant usage patterns.