Export Preflight Disk Guard
Catch the "stuck at 99%" class of export failures before they happen
Exports hang or fail late in the process — often near completion — due to insufficient free space, problematic clips, or unstable settings. This recipe checks disk space, validates export targets, and provides a fallback render path before you waste an hour waiting for a doomed export.
INGREDIENTS
PROMPT
Create a skill called "Export Preflight Disk Guard". Ask me for: - export_path - duration_minutes (or media file/timeline export to infer) - target_bitrate_mbps - safety_multiplier and buffer_gb Then: - Estimate output size, check free space, warn early. - If I choose, generate a fallback plan: export mezzanine then ffmpeg transcode.
How It Works
This skill estimates your export output size, checks free disk space with a safety
multiplier, and writes a pre-export checklist. If an export fails, it provides a fallback
strategy: export a mezzanine intermediate first, then transcode to final delivery format
with ffmpeg.
What You Get
- Output size estimate based on duration, bitrate, and safety multiplier
- Free space check with early warning before you start the export
- Pre-export checklist: proxy/original mode, cache health, codec settings
- Fallback strategy: mezzanine export (ProRes/DNxHR) → ffmpeg transcode to H.264/H.265
- Segment isolation guide for repeated failures (export in chunks to find the bad section)
Setup Steps
- Set your export path and provide duration + target bitrate (or let it infer from your preset)
- Configure safety multiplier (default 2x) and buffer (default 20GB)
- Run before every export, or set up a watcher on your export queue folder
Tips
- A 42-minute timeline at 25 Mbps needs ~8GB, but intermediate files during export can double that
- The mezzanine-then-transcode fallback is slower but far more reliable than fighting a codec bug
- If exports keep dying at the same spot, use the segment isolation guide to find the toxic clip or effect
- Pair with Proxy-to-Original Integrity Check to confirm your export source is correct before starting