asciinema-cast-format

Reference documentation for the asciinema v3 .cast file format (asciicast v2 specification).

Platform: All platforms (documentation only)

Self-Evolving Skill: This skill improves through use. If instructions are wrong, parameters drifted, or a workaround was needed — fix this file immediately, don't defer. Only update for real, reproducible issues.

When to Use This Skill

Use this skill when:

• Parsing or inspecting .cast file structure
• Understanding NDJSON header and event formats
• Building tools that read or write .cast files
• Debugging recording issues or format errors
• Learning the asciicast v2 specification