Episode generation has two stages that can fail separately: writing the script, and rendering the audio. Each shows a different signal and has its own retry path. If you landed here because an episode has been stuck in Draft, see Why is my episode still a draft? first.
If generation never starts
If starting generation fails before an episode even exists, the error appears right on the generation form itself, not on an episode page. You will see a message such as "Failed to start generation." Fix whatever the message points to and try again from the same form.
If the script failed
Open the episode and check the Overview tab for a script diagnostics card. When a script run failed or was blocked, the card explains why in plain language rather than a raw error code. The headline names the actual problem, for example:
- The script repeated too much of a recent episode
- The script drifted from what you asked for
- The script tried to cover too much for its runtime
- The script did not build from one point to the next
- The script made a claim the sources did not back up
- The script leaned on weak sources
- Script generation stopped before it finished (a technical failure rather than an editorial one)
Editorial reasons (repetition, drift, weak sourcing) suggest regenerating the script or generating the episode again with a different angle. Technical or pipeline reasons mean the run stopped for a reason unrelated to content quality, and generating again is usually the fastest fix.
Click Regenerate script on the diagnostics card to try again. This button is only available before audio production has started on that script. Once audio generation has begun, the script locks and a rerun is no longer available from this card.
A failed script run does not change the episode's status pill. You will only see it by opening the episode and checking this card, since the episode list has no separate "failed" filter.
If audio generation failed
If the script succeeded but audio failed, the Overview tab shows a red banner: "Audio generation failed." If Mato captured a specific reason, it appears there; otherwise you will see a generic prompt to review the script or retry.
To retry, use the Generate audio (or Regenerate audio) action on the episode. By default, regeneration is incremental: it only re-renders the sections whose script text changed since the last successful render, and reuses audio for everything else. This is faster, but it also means that if the problem is in a section you have not edited, a plain regenerate will not touch it. Either edit that section's text so it is picked up, or use Force full regen if your role allows it (workspace owners, admins, and Mato staff only) to rebuild every section from scratch.
If your script does not use section markers such as [INTRO], [SEGMENT 1: Title], and [OUTRO], regeneration warns you that it will treat the whole script as one block: no chapter markers, no per-section parallel generation, and no background overlays per section. Adding markers before you regenerate gets you a better structured result.
Where to look, in order
- Episode Overview tab: script diagnostics card (script failures) and the audio failure banner (audio failures).
- If the retry button is missing or the script looks locked, audio production has probably already started; check the audio section instead of trying to force a script rerun.
- If a fix does not stick after a couple of attempts, contact Mato support with the episode's URL and, if shown, the exact failure headline.