> ## Documentation Index
> Fetch the complete documentation index at: https://heygen-1fa696a7.mintlify.site/llms.txt
> Use this file to discover all available pages before exploring further.

# Apply a Glossary

> Pass a brand_glossary_id on HeyGen videos, templates, Video Agent sessions, batches, and video translations so your terms are spoken and translated your way.

![](https://mintcdn.com/heygen-1fa696a7/hfMXXwJzjE7vBSYZ/images/theme/research.webp?fit=max\&auto=format\&n=hfMXXwJzjE7vBSYZ\&q=85\&s=3e4c2594813dcfd56985f3d63e3ba321)

Pass `brand_glossary_id` at the top level of the request, one glossary per call:

```bash theme={null}
curl -X POST "https://api.heygen.com/v3/videos" \
  -H "X-Api-Key: $HEYGEN_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "type": "avatar",
    "brand_glossary_id": "8c2d5e91a47b4f3c8d1e6a9b2f5c7d40",
    "avatar_id": "YOUR_AVATAR_ID",
    "script": "HeyGen shipped this in 2024.",
    "voice_id": "YOUR_VOICE_ID"
  }'
```

| Where | What the glossary does |
| - | - |
| [`POST /v3/videos`](https://heygen-1fa696a7.mintlify.site/reference/create-video) with `"type"` of `studio`, `avatar`, or `image` | [Pronunciations](https://heygen-1fa696a7.mintlify.site/docs/brand-glossary/pronunciations.md) wherever audio is synthesized from a `script` |
| [`POST /v3/videos/batches`](https://heygen-1fa696a7.mintlify.site/reference/create-video-batch) | Same, set per item |
| [`POST /v3/templates/{template_id}`](https://heygen-1fa696a7.mintlify.site/reference/generate-video-from-template) | Pronunciations in the template's speech |
| [`POST /v3/video-agents`](https://heygen-1fa696a7.mintlify.site/reference/create-video-agent-session) | Pronunciations in the narration, set once per session alongside an optional [brand kit](https://heygen-1fa696a7.mintlify.site/docs/brand-kits.md) |
| [`POST /v3/video-translations`](https://heygen-1fa696a7.mintlify.site/reference/create-video-translation) and [batches](https://heygen-1fa696a7.mintlify.site/batch-video-translations.md) | [Translation rules](https://heygen-1fa696a7.mintlify.site/docs/brand-glossary/translation-rules.md) in the translated script, set per item in a batch |
| [`POST /v3/video-translations/proofreads`](https://heygen-1fa696a7.mintlify.site/reference/create-proofread-session) | Translation rules in the editable subtitles |

[On Brand](https://heygen-1fa696a7.mintlify.site/docs/on-brand.md) covers how the glossary and brand kit divide the work. Scenes with their own `audio_url` or `audio_asset_id` play that audio as supplied, and captions keep the original script wording.

An unknown `brand_glossary_id` fails the request with `400` before rendering, so no credits are spent. Glossaries are workspace-scoped: an ID from another workspace is rejected, so use an API key from the workspace that owns the glossary.


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