Action chapters are supposed to move, but speed on the page is rarely as simple as adding shorter sentences and more explosions. A fight can contain constant motion and still feel slow if the reader is processing repeated information, unnecessary explanation, or too many pauses between meaningful changes.

This is where AI can become a useful revision tool. Instead of asking it to rewrite the scene, I prefer using it as an auditor. Give it an action chapter and ask it to identify where momentum rises, stalls, and changes direction. Have it flag moments where characters repeat decisions, descriptions interrupt urgent movement, or several paragraphs pass without the situation becoming more dangerous, complicated, or surprising.

There is some encouraging research behind that approach. A 2025 ACL study tested large language models on 1,300 deliberately flawed stories and found that they could often provide specific, mostly accurate writing feedback. The catch was important: the models did not always recognize the biggest problem in a story.

Treat the AI Like a Second Reader

That limitation is exactly why pacing audits work best as diagnosis rather than instruction.

If an AI flags three slow sections, I do not automatically cut them. I ask why they were flagged. Perhaps a paragraph of internal thought interrupts a chase—but that pause might be the emotional reason the chase matters. The useful information is not “delete this.” It is “the perceived momentum changed here.”

Research into AI-assisted revision has similarly shown that detailed criteria improve the usefulness of automated evaluation. One study found GPT-4 particularly promising when researchers supplied explicit rubrics describing revision patterns.

For action scenes, that means giving the AI a job: track escalation, interruptions, repeated beats, sentence rhythm, and stretches where nothing materially changes.

The machine can point at the speed bumps. The writer still decides whether they belong in the road.