HeyGen and Google Veo: pipeline hooks

HeyGen and Google Veo document different things on seven of the nine hooks: agent hooks, resolution, subtitle files, downloads, file formats, SDKs and job signals. From 3 source pages, read 2026-09-25; no maker pays to be listed.

Fig. 1 Solid: documented. Outline: nothing read.

HeyGen and Google Veo, feature by feature, read 2026-09-25.
Feature	HeyGen	Google Veo
Public API	An API for its own models	An API for its own models
Agent and automation hooks	An MCP connection	Not documented in the docs read
Highest resolution named	Not documented in the docs read	4K
Hand-off to editing software	Not documented in the docs read	Not documented in the docs read
Subtitle files	SRT and VTT files	Not documented in the docs read
The finished file	A file fetched from the API	A link or file that expires
File formats named	MP4	Not documented in the docs read
Official SDKs	Not documented in the docs read	SDKs in two or more languages
Finished-job signal	A webhook or callback URL	A status polled until done

Inclusion rule. The nine hooks every tool in the register is read for. Order. The order hooks take on every tool page.

1Where they part

HeyGen documents agent hooks, subtitle files and file formats, which Google Veo's pages leave out. Google Veo documents resolution and SDKs, which HeyGen's pages leave out. For API access the two match: an API for its own models. For downloads, HeyGen names a file fetched from the API and Google Veo a link or file that expires. For job signals, HeyGen names a webhook or callback URL and Google Veo a status polled until done. Neither documents editing hand-off.

2From each tool's documentation

Subtitle files

Captions are generated in SRT and VTT.
HeyGen, developer documentation: video translation

Google Veo's documentation read says nothing here.

The finished file

carries them as presigned download URLs alongside the video
HeyGen, developer documentation: video translation

Generated videos are stored on the server for 2 days, after which they are removed.
Google, Gemini API documentation: Veo

Finished-job signal

Batch APIs — up to 100 requests per call, webhooks included
HeyGen, developer site

Poll the operation status until the video is ready.
Google, Gemini API documentation: Veo

Captions
Captions generated as SRT and VTT files for translated videosHeyGen, developer documentation: video translation / recorded 2026-09-25
Captions
Video and caption files returned as presigned download URLsHeyGen, developer documentation: video translation / recorded 2026-09-25
Limitations
Generated videos kept on the server for two days, then removedGoogle, Gemini API documentation: Veo / recorded 2026-09-25
Features
Batch APIs of up to 100 requests per call, with webhooksHeyGen, developer site / recorded 2026-09-25
Generating videos
The operation status polled until the video is readyGoogle, Gemini API documentation: Veo / recorded 2026-09-25

3A third tool on getting the file out, beside HeyGen and Google Veo

What SceneMixer's page says on a field where HeyGen and Google Veo differ, read 2026-09-25.
Field	SceneMixer	Source
The finished file	A full-quality download and a share link; the browser plays a lighter copy	SceneMixer, guide to compositing and sharing an episode

Inclusion rule. Fields on which SceneMixer's pages state something; most toolkit fields are not its subject. Order. The order fields take on every tool page.