MiniMax H3 API
Every input field of MiniMax H3, the rules between them, the price and a complete request with its responses.
"model": "minimax-h3"Generates a video from one prompt text plus optional image frames, or reference images, videos and audio.
What it does
MiniMax H3 makes a 768P video of 4 to 15 seconds from a prompt and optional media. Everything goes in one list, input.content: exactly one text item carries the prompt, and each image_url, video_url and audio_url item names its role. resolution (always 768P) and duration are required. The items you send choose the mode:
| Mode | content items | Other fields to set |
|---|---|---|
| [Text to video](#text-to-video) | text | ratio other than adaptive |
| [First frame](#first-frame) | text, one image_url with role first_frame | — |
| [First and last frame](#first-and-last-frame) | text, first_frame and last_frame images | — |
| [Reference images](#reference-images) | text, 1 to 5 image_url with role reference_image | — |
| [Reference video and audio](#reference-video-and-audio) | text, any mix of reference images, up to 3 video_url with role reference_video, up to 3 audio_url with role reference_audio | — |
Every example below is a complete body for POST /v1/generations. Send the same body to POST /v1/estimates first: it is free, creates no task, holds no Credits, and refuses an invalid body with the same 422 as a create. The https://media.vizoapi.com/... files are public samples, so the examples run as they are; replace https://example.com/... with your own file or an uploaded ast_... asset ID.
Modes
Text to video
Only the text item. Set ratio to 21:9, 16:9, 4:3, 1:1, 3:4 or 9:16: without media, adaptive or no ratio is refused (rule ratio_required).
{
"model": "minimax-h3",
"input": {
"content": [
{ "type": "text", "text": "A paper boat drifts across a still pond at dawn, mist on the water, slow push-in, soft natural light" }
],
"resolution": "768P",
"duration": 6,
"ratio": "16:9"
}
}First frame
The video starts on your image. Send one image_url with role first_frame. The output always takes the image's shape: with frames, any ratio you send is replaced by adaptive. The prompt describes what happens next.
{
"model": "minimax-h3",
"input": {
"content": [
{ "type": "text", "text": "The hominids step back as the sun rises behind the monolith, slow push-in" },
{ "type": "image_url", "role": "first_frame", "image_url": { "url": "https://media.vizoapi.com/samples/seedance-2-5/odyssey-v1/keyframes/monolith.jpg" } }
],
"resolution": "768P",
"duration": 6
}
}First and last frame
The video moves from the first image to the last. Send at most one first_frame and one last_frame (rule frame_repeated). Frames cannot be combined with any reference image, video or audio (rule frames_with_references).
{
"model": "minimax-h3",
"input": {
"content": [
{ "type": "text", "text": "The ring-shaped station slowly turns to face the camera as an amber planet rises behind it" },
{ "type": "image_url", "role": "first_frame", "image_url": { "url": "https://media.vizoapi.com/samples/seedance-2-5/odyssey-v1/keyframes/station.jpg" } },
{ "type": "image_url", "role": "last_frame", "image_url": { "url": "https://media.vizoapi.com/samples/seedance-2-5/odyssey-v1/keyframes/ending.jpg" } }
],
"resolution": "768P",
"duration": 6
}
}Reference images
Up to 5 images with role reference_image give the model characters, objects, places or a style to reuse; they do not fix any frame (rule too_many_images, which counts every image). ratio is optional: adaptive (the default) follows the input, or pick a fixed one.
{
"model": "minimax-h3",
"input": {
"content": [
{ "type": "text", "text": "Shot 1: the black monolith from image 1 stands on a savanna at dawn. Shot 2: match cut to the ring-shaped space station from image 2, tumbling slowly in black space." },
{ "type": "image_url", "role": "reference_image", "image_url": { "url": "https://media.vizoapi.com/samples/seedance-2-5/odyssey-v1/keyframes/monolith.jpg" } },
{ "type": "image_url", "role": "reference_image", "image_url": { "url": "https://media.vizoapi.com/samples/seedance-2-5/odyssey-v1/keyframes/station.jpg" } }
],
"resolution": "768P",
"duration": 8,
"ratio": "16:9"
}
}Reference video and audio
Reference videos give motion, camera movement or a subject; reference audio gives a voice, rhythm or sound. Send up to 3 videos (rule too_many_videos), each 2 to 15 seconds and 15 seconds together, and up to 3 audio items (rule too_many_audios), 15 seconds together. They mix freely with reference images. Any video_url moves the task to the 768p-video tier, which bills the input video's seconds too (see [How it is billed](#how-it-is-billed)); audio never changes the tier.
Reference video
{
"model": "minimax-h3",
"input": {
"content": [
{ "type": "text", "text": "Follow the camera movement and pacing of video 1, set on the space station from image 1" },
{ "type": "image_url", "role": "reference_image", "image_url": { "url": "https://media.vizoapi.com/samples/seedance-2-5/odyssey-v1/keyframes/station.jpg" } },
{ "type": "video_url", "role": "reference_video", "video_url": { "url": "https://media.vizoapi.com/samples/seedance-2-5/odyssey-v1/1.mp4" } }
],
"resolution": "768P",
"duration": 5,
"ratio": "16:9"
}
}Reference audio
{
"model": "minimax-h3",
"input": {
"content": [
{ "type": "text", "text": "The astronaut from image 1 speaks to the camera inside the station, in the voice of audio 1" },
{ "type": "image_url", "role": "reference_image", "image_url": { "url": "https://example.com/astronaut.png" } },
{ "type": "audio_url", "role": "reference_audio", "audio_url": { "url": "https://example.com/voice.mp3" } }
],
"resolution": "768P",
"duration": 8,
"ratio": "16:9"
}
}Input limits
| Limit | Value | Checked |
|---|---|---|
content items | 1 to 16. Exactly one text item; up to 5 images, 3 videos and 3 audio items | At create, 422 invalid_input (too_many_items, too_few_items, text_count, too_many_images, too_many_videos, too_many_audios) |
| Prompt | Up to 7,000 characters | At create (out_of_range) |
| Roles | Every image, video and audio item needs role: first_frame, last_frame or reference_image for images, reference_video for video, reference_audio for audio. Frames (one of each at most) never mix with references | At create (role_required, role_not_allowed, frame_repeated, frames_with_references) |
| Each video | 2 to 15 seconds | At create when the file's length can be read, 422 input_duration_out_of_range (video_length); otherwise when the task runs |
| All videos together | At most 15 seconds | Same, rule video_total_too_long |
| All audio together | At most 15 seconds | Same, rule audio_total_too_long |
| Image file | PNG, JPEG, WebP, HEIC; up to 30 MB | At create when readable: 422 input_media_invalid (format) or input_media_too_large (size) |
| Video file | MP4, MOV; up to 50 MB | Same |
| Audio file | MP3, WAV; up to 15 MB | Same |
| Uploaded asset | image/png, image/jpeg, image/webp, video/mp4, audio/mpeg, audio/wav; up to 20,000,000 bytes | When you request the upload, 422 |
| Image 256 to 5,760 pixels per side and aspect ratio 0.4 to 2.5; each audio item 2 to 15 seconds | Checked by the model only | When the task runs: the task fails with generation_failed and is not charged |
A media value is a public https URL (up to 4,000 characters) or an ast_... asset ID from your project. Plain http, private or local addresses, URLs with a user name or #fragment, and Base64 data are refused with 422 (rule bad_format). The model fetches a linked file itself, possibly some time after acceptance, so keep it reachable until the task closes. See Model inputs and media.
Output
| Setting | Values |
|---|---|
resolution | Required, only 768P (case-sensitive) |
duration | Required, 4 to 15 seconds. There is no automatic length |
ratio | adaptive (default), 21:9, 16:9, 4:3, 1:1, 3:4 or 9:16. Text alone needs a fixed ratio; with frames it is always adaptive |
aigc_watermark | false (default) or true for a visible AI-generated mark. The price is the same |
A succeeded task lists one MP4 in result.outputs: take its asset_id and get a download URL with download an asset. Outputs are kept for 7 days. See Get results.
How it is billed
The input selects the tier: 768p, or 768p-video when content has any video_url. Both have the same rate per second, but the video tier also bills the input video's seconds. Images and audio never change the tier or the price, and neither do ratio or aigc_watermark.
| Tier | Credits per second | Seconds billed |
|---|---|---|
768p | 18 | Output seconds |
768p-video | 18 | Output + input seconds |
Input seconds are the length of all videos together, rounded up, at most 15. When a video's length cannot be read at create, the hold counts 15 input seconds. The sample video in the examples runs 12.06 seconds, so it holds 13 input seconds.
| Request | Output | Input | Billed | Held (Credits) |
|---|---|---|---|---|
Text, frames or reference images, duration: 6 | 6 | — | 6 | 108.000 |
The same, duration: 15 | 15 | — | 15 | 270.000 |
Reference video of 12.06 s, duration: 5 | 5 | 13 | 18 | 324.000 |
| The same, video length not readable | 5 | 15 | 20 | 360.000 |
The hold is only the estimate. A succeeded task is charged for the output seconds the model reports, plus its reported input seconds on the video tier, to the millisecond, at the tier's rate. So price.charged can be below the hold (the rest is released) or above it, with no cap. When the model reports no output length, or on the video tier the input length is known neither from the model nor from the create, the charge is the hold. Usage above the hold comes from your available balance; what it cannot cover is owed, and new creates get 402 balance_negative until a top-up. A failed or unresolved task is not charged. Send the body to POST /v1/estimates to see the exact hold and its basis (output_seconds, input_seconds, billed_seconds). See Billing.
Errors and behaviors
| When | Response | What to do |
|---|---|---|
A field the schema does not list, a wrong value or type, no resolution or duration | 422 invalid_input, errors[].rule such as field_not_allowed, value_not_allowed, out_of_range, required | Send only the fields in the reference below |
More than 16 content items, or an empty list | 422 invalid_input, rule too_many_items or too_few_items | Send 1 to 16 items |
| A content rule is broken | 422 invalid_input with the rule: text_count, role_required, role_not_allowed, frame_repeated, frames_with_references, too_many_images, too_many_videos, too_many_audios | Fix the item at errors[].path |
Text alone with ratio adaptive or none | 422 invalid_input, rule ratio_required | Set a fixed ratio |
| A measured video is too short or too long, or measured videos or audio are too long in total | 422 input_duration_out_of_range; errors[] names the item (/content/N/video_url/url, rule video_length) or the total (/content, rule video_total_too_long or audio_total_too_long) | Trim the media |
| A linked file has the wrong format or is too large | 422 input_media_invalid or input_media_too_large | Convert or shrink it |
| Content safety refuses the prompt or media | Task fails with input_moderated when the model reports a safety refusal; otherwise generation_failed | Change the prompt or media; nothing is charged |
| Content safety refuses the result | Task fails with output_moderated when the model reports a safety refusal; otherwise generation_failed; no result | Change the prompt; nothing is charged |
| The model refuses the request when it is sent | Task fails with generation_failed | Check the body against the limits above; nothing is charged |
| The model refuses a file or setting when the task runs, or cannot fetch a URL | Task fails with generation_failed; input_media_invalid or input_media_unreachable when the model names that cause | Check the media against the limits above and keep URLs public; nothing is charged |
| The model fails for another reason | Task fails with generation_failed | Retry, or change the prompt; nothing is charged |
Moderation is always on; no field turns it off. Each task has a deadline of 24 hours from acceptance. A task still unfinished then closes as unresolved, releases its hold and is not charged; if its result arrives later, it is added at no charge and late_result_available becomes true. See Errors and Get results.
Prompting tips
- Name reference media by kind and order in
content: "image 1", "image 2", "video 1", "audio 1". Say what to take from each: "the character from image 1", "the camera movement of video 1", "the voice of audio 1". - Write the shot, not just the subject: subject, action, setting, camera movement, light and style, in that order.
- With first and last frames, describe the motion between them; the frames already fix the start and end, and the shape follows the first image.
- Always set
ratiofor a prompt alone: without media,adaptiveis refused. - Videos are at most 15 seconds: for a longer piece, generate several shots and join them, with a still from the end of one shot as the next shot's
first_frame.
Pricing
Your input selects the tier. Video is billed per second of output; a tier with input video also counts the input seconds.
| Tier | Selected by | Price | Length |
|---|---|---|---|
768p | resolution = 768p | 18 Credits/s | 4–15 s |
768p-video | resolution = 768p, input video | 18 Credits/s | 4–15 s |
Rules
contentholds exactly onetextitem.- Every image, video and audio item in
contentnames itsrole. - Frames (
first_frame,last_frame, at most one each) cannot be combined with reference images, videos or audio. - Input without images, videos or audio needs a
ratioother thanadaptive; input with frames always usesadaptive. resolutionis case-sensitive: send768P.
Input fields
Send these fields in input. A field the table does not list is refused with HTTP 422 invalid_input.
| Field | Description |
|---|---|
| Exactly one text item. Frames (first_frame, last_frame, at most 1 each) cannot be combined with references. Up to 5 images, 3 videos (2 to 15 seconds each, 15 in total) and 3 audios (15 seconds in total). At least 1 items · At most 16 items |
content[]. | Item kind. Allowed values textimage_urlvideo_urlaudio_url |
Items where type is text | |
content[]. | Prompt text, up to 7000 characters. At most 7000 characters |
Items where type is image_url | |
content[]. | Image roles: first_frame, last_frame, reference_image. Video: reference_video. Audio: reference_audio. |
content[]. | |
content[]. | An https URL or an uploaded asset id (ast_...). At most 4000 characters · Pattern |
Items where type is video_url | |
content[]. | Image roles: first_frame, last_frame, reference_image. Video: reference_video. Audio: reference_audio. |
content[]. | |
content[]. | An https URL or an uploaded asset id (ast_...). At most 4000 characters · Pattern |
Items where type is audio_url | |
content[]. | Image roles: first_frame, last_frame, reference_image. Video: reference_video. Audio: reference_audio. |
content[]. | |
content[]. | An https URL or an uploaded asset id (ast_...). At most 4000 characters · Pattern |
| Output resolution. Only 768P. Only |
| Output length in seconds, 4 to 15. Minimum 4 · Maximum 15 |
| Output aspect ratio. Text-only input needs a value other than adaptive; input with frames always uses adaptive. Allowed values adaptive21:916:94:31:13:49:16Default |
| Add a visible watermark. Defaults to false; the tier price is unchanged. Default |
Example
A complete create request, the 202 answer and the task once it has succeeded.
Request
cURL
curl https://api.vizoapi.com/v1/generations \
-H "Authorization: Bearer $VIZO_API_KEY" \
-H "Content-Type: application/json" \
-d '{
"model": "minimax-h3",
"input": {
"content": [
{
"type": "text",
"text": "A paper boat drifting on a pond at dawn, slow dolly in"
}
],
"resolution": "768P",
"ratio": "16:9",
"duration": 6
},
"metadata": {
"client_reference": "my-unique-reference-1"
}
}'Python
import os, requests
# Send once: do not retry this request automatically.
task = requests.post(
"https://api.vizoapi.com/v1/generations",
headers={"Authorization": f"Bearer {os.environ['VIZO_API_KEY']}"},
json={
"model": "minimax-h3",
"input": {
"content": [
{
"type": "text",
"text": "A paper boat drifting on a pond at dawn, slow dolly in"
}
],
"resolution": "768P",
"ratio": "16:9",
"duration": 6
},
"metadata": {
"client_reference": "my-unique-reference-1"
}
},
timeout=60,
).json()
print(task["id"], task["status"])Node.js
// Send once: do not retry this request automatically.
const res = await fetch("https://api.vizoapi.com/v1/generations", {
method: "POST",
headers: {
Authorization: `Bearer ${process.env.VIZO_API_KEY}`,
"Content-Type": "application/json",
},
body: JSON.stringify({
"model": "minimax-h3",
"input": {
"content": [
{
"type": "text",
"text": "A paper boat drifting on a pond at dawn, slow dolly in"
}
],
"resolution": "768P",
"ratio": "16:9",
"duration": 6
},
"metadata": {
"client_reference": "my-unique-reference-1"
}
}),
});
const task = await res.json();
console.log(task.id, task.status);This input selects the 768p tier at 18 Credits per second. For 6 seconds the API holds 108.000 Credits.
Response
202 Accepted
{
"id": "gen_01JD8Z5QW3XR",
"model": "minimax-h3",
"source": "api",
"created_at": "2026-11-08T09:00:00Z",
"customer_resolution_deadline": "2026-11-09T09:00:00Z",
"late_result_available": false,
"metadata": {
"client_reference": "my-unique-reference-1"
},
"status": "processing",
"execution_status": "processing",
"delivery_status": "pending",
"billing_status": "pending",
"version": 1,
"price": {
"unit": "credit",
"estimated": "108.000",
"reserved": "0.000",
"charged": "0.000",
"refunded": "0.000"
},
"allowed_actions": [],
"closed_at": null,
"error": null,
"result": null
}200 Succeeded
{
"id": "gen_01JD8Z5QW3XR",
"model": "minimax-h3",
"source": "api",
"created_at": "2026-11-08T09:00:00Z",
"customer_resolution_deadline": "2026-11-09T09:00:00Z",
"late_result_available": false,
"metadata": {
"client_reference": "my-unique-reference-1"
},
"status": "succeeded",
"execution_status": "succeeded",
"delivery_status": "ready",
"billing_status": "settled",
"version": 4,
"price": {
"unit": "credit",
"estimated": "108.000",
"reserved": "0.000",
"charged": "108.000",
"refunded": "0.000"
},
"allowed_actions": [],
"closed_at": "2026-11-08T09:01:31Z",
"error": null,
"result": {
"asset_id": "ast_01JD8Z9M2C4V",
"outputs": [
{
"index": 0,
"asset_id": "ast_01JD8Z9M2C4V",
"content_type": "video/mp4"
}
]
}
}