> ## Documentation Index > Fetch the complete documentation index at: https://evolink.ai/docs/llms.txt > Use this file to discover all available pages before exploring further. # Minimax H3 Complete Parameter Guide > Unified API for the entire Minimax H3 series. Select the generation mode with the `model` parameter. **3 generation modes:** | Mode | Model ID | Input assets | |:---|:---|:---| | Text-to-Video | `minimax-h3-text-to-video` | `prompt` only | | Image-to-Video | `minimax-h3-image-to-video` | `prompt` + `image_start` and/or `image_end` | | Reference-to-Video | `minimax-h3-reference-to-video` | `prompt` + `image_urls` / `video_urls` / `audio_urls` | **Shared capabilities:** - Output duration from `5` to `15` seconds; currently only `2k` is supported - Asynchronous processing; use the returned task ID to [query the task](/en/api-manual/task-management/get-task-detail) - Minimax H3 tasks cannot be canceled - Generated video URLs remain valid for 24 hours; save the result promptly ## OpenAPI ````yaml en/api-manual/video-series/minimax/minimax-h3/minimax-h3-overview.json POST /v1/videos/generations openapi: 3.1.0 info: title: Minimax H3 All Models API description: >- Unified API for all 3 Minimax H3 models, covering text-to-video, image-to-video, and multimodal reference-to-video generation license: name: MIT version: 1.0.0 servers: - url: https://api.evolink.ai description: Production security: - bearerAuth: [] tags: - name: Video Generation description: AI video generation endpoints paths: /v1/videos/generations: post: tags: - Video Generation summary: Minimax H3 Video Generation (All Models) description: >- Unified API for the entire Minimax H3 series. Select the generation mode with the `model` parameter. **3 generation modes:** | Mode | Model ID | Input assets | |:---|:---|:---| | Text-to-Video | `minimax-h3-text-to-video` | `prompt` only | | Image-to-Video | `minimax-h3-image-to-video` | `prompt` + `image_start` and/or `image_end` | | Reference-to-Video | `minimax-h3-reference-to-video` | `prompt` + `image_urls` / `video_urls` / `audio_urls` | **Shared capabilities:** - Output duration from `5` to `15` seconds; currently only `2k` is supported - Asynchronous processing; use the returned task ID to [query the task](/en/api-manual/task-management/get-task-detail) - Minimax H3 tasks cannot be canceled - Generated video URLs remain valid for 24 hours; save the result promptly operationId: createMinimaxH3VideoGeneration requestBody: required: true content: application/json: schema: $ref: '#/components/schemas/VideoGenerationRequest' examples: text_to_video: summary: Text-to-video value: model: minimax-h3-text-to-video prompt: >- Epic space-opera trailer: a female captain stands alone before a vast observation window as the last fleet assembles outside. The fleet jumps in a blinding white flash and the bridge shakes violently; when the light fades, she is left alone in silent deep space. Cinematic lighting, slow push-in, grand yet restrained atmosphere. duration: 5 quality: 2k aspect_ratio: '16:9' image_to_video: summary: Image-to-video (first-frame driven) value: model: minimax-h3-image-to-video prompt: >- Shift focus slowly from the bowl of ramen in the foreground to the person in the background. Steam keeps rising from the bowl and drifts naturally through the air. Push the camera forward slightly while preserving the person's identity and the restaurant environment. image_start: >- https://cdn.hailuoai.com/prod/hailuo_demo/testsets/H3_AA_I2VA/gallery/sr_v17_variants_seed42_43_20260724/inputs/4a3a90bf9100_KDmcbkhzYo5sjjxr9FqcVmWVnzb.png duration: 5 quality: 2k reference_to_video: summary: Multimodal reference (image + video + audio) value: model: minimax-h3-reference-to-video prompt: >- Replace the person in Video 1 with the character from Image 1, preserving the face, hairstyle, and clothing from Image 1. Retain the complete motion, pacing, composition, and camera work from Video 1, and perform the dialogue with the voice from Audio 1 while keeping the lip movements synchronized. image_urls: - >- https://cdn.hailuoai.com/prod/hailuo_demo/testsets/H3_AA_I2VA/gallery/sr_v17_variants_seed42_43_20260724/inputs/4a3a90bf9100_KDmcbkhzYo5sjjxr9FqcVmWVnzb.png video_urls: - >- https://cdn.hailuoai.com/prod/hailuo_demo/testsets/h3_promo_eval_ref2va/gallery/sr_v2p26_trio_seed42_20260724/inputs/297573323635_00_%E8%A7%86%E9%A2%911_YnyRbxEwio_video_20260525_163755_1927e9d3.mp4 audio_urls: - >- https://cdn.hailuoai.com/prod/hailuo_demo/testsets/h3_promo_eval_ref2va/gallery/sr_v2p26_trio_seed42_20260724/inputs/f463d523c5ce_01_%E9%9F%B3%E9%A2%911_RSLcbpzJPo_6%E6%9C%885%E6%97%A5(1).mp3 duration: 5 quality: 2k aspect_ratio: adaptive responses: '200': description: Video generation task created successfully content: application/json: schema: $ref: '#/components/schemas/VideoGenerationResponse' '400': description: Invalid request parameters content: application/json: schema: $ref: '#/components/schemas/ErrorResponse' example: error: code: invalid_request message: Invalid request parameters type: invalid_request_error '401': description: Unauthenticated, token invalid or expired content: application/json: schema: $ref: '#/components/schemas/ErrorResponse' example: error: code: unauthorized message: Invalid or expired token type: authentication_error '402': description: Insufficient quota, top-up required content: application/json: schema: $ref: '#/components/schemas/ErrorResponse' example: error: code: insufficient_quota message: Insufficient quota. Please top up your account. type: insufficient_quota '403': description: Access denied content: application/json: schema: $ref: '#/components/schemas/ErrorResponse' example: error: code: model_access_denied message: >- Token does not have access to model: minimax-h3-text-to-video type: invalid_request_error '429': description: Rate limit exceeded content: application/json: schema: $ref: '#/components/schemas/ErrorResponse' example: error: code: rate_limit_exceeded message: Too many requests, please try again later type: rate_limit_error '500': description: Internal server error content: application/json: schema: $ref: '#/components/schemas/ErrorResponse' example: error: code: internal_error message: Internal server error type: api_error components: schemas: VideoGenerationRequest: type: object required: - model - prompt properties: model: type: string description: >- Video generation model name. | Model ID | Mode | Asset parameters | |:---|:---|:---| | `minimax-h3-text-to-video` | Text-to-video | Does not accept media assets | | `minimax-h3-image-to-video` | Image-to-video | `image_start` and/or `image_end` | | `minimax-h3-reference-to-video` | Multimodal reference-to-video | `image_urls` / `video_urls` / `audio_urls` | enum: - minimax-h3-text-to-video - minimax-h3-image-to-video - minimax-h3-reference-to-video example: minimax-h3-text-to-video prompt: type: string minLength: 1 description: >- Describe the video you want to generate. This field is required and cannot be empty. **Prompt requirements:** - Chinese and English are supported - We recommend no more than `500` Chinese characters or `1000` English words; the model may ignore some details in an overly long prompt **Usage by model:** - **Text-to-Video:** Describe the scene, subject, action, camera, and mood. Do not provide any media fields - **Image-to-Video:** Describe how subjects in the first/last frame should move and how the camera should change; use `image_start` and/or `image_end` - **Reference-to-Video:** Describe how to use the reference assets. Refer to them as `Image 1`, `Image 2`, `Video 1`, `Audio 1`, and so on; do not use Seedance-style names such as `@image1` or `@video1`. Numbering starts at `1` and follows the order of each URL array example: >- Cinematic scene: an astronaut stands before the observation window of a lunar base as the camera slowly pushes in and Earth rises above the distant horizon. image_start: type: string format: uri description: >- **Applicable models:** - Only `minimax-h3-image-to-video` - Text-to-video and reference-to-video do not support this parameter HTTP(S) URL of the first-frame image. **Combination rules:** - Provide at least one of `image_start` and `image_end` - `image_start` only: first-frame image-to-video - Both fields: first-and-last-frame image-to-video - At most `1` first frame; this field accepts one URL **Image requirements:** - Formats: JPG, JPEG, PNG, WEBP, HEIC, HEIF - File size: no more than `30MB` - Width and height: each from `256` to `5760` px - Aspect ratio (width/height): `0.4`–`2.5` - The URL must use HTTP(S) and be directly accessible by the service - The complete JSON request body must not exceed `64MB`; Base64 and `mm_file://` inputs are not accepted example: >- https://cdn.hailuoai.com/prod/hailuo_demo/testsets/H3_AA_I2VA/gallery/sr_v17_variants_seed42_43_20260724/inputs/4a3a90bf9100_KDmcbkhzYo5sjjxr9FqcVmWVnzb.png image_end: type: string format: uri description: >- **Applicable models:** - Only `minimax-h3-image-to-video` - Text-to-video and reference-to-video do not support this parameter HTTP(S) URL of the last-frame image. **Combination rules:** - Provide at least one of `image_end` and `image_start` - `image_end` only: the model generates natural motion that ends on this frame - Both fields: first-and-last-frame image-to-video - At most `1` last frame; this field accepts one URL **Image requirements:** - Formats: JPG, JPEG, PNG, WEBP, HEIC, HEIF - File size: no more than `30MB` - Width and height: each from `256` to `5760` px - Aspect ratio (width/height): `0.4`–`2.5` - The URL must use HTTP(S) and be directly accessible by the service - The complete JSON request body must not exceed `64MB`; Base64 and `mm_file://` inputs are not accepted example: >- https://images.unsplash.com/photo-1515003197210-e0cd71810b5f?auto=format&fit=crop&w=1920&q=85 image_urls: type: array description: >- **Applicable models:** - Only `minimax-h3-reference-to-video` - Text-to-video and image-to-video do not support this parameter Array of HTTP(S) reference-image URLs. Defaults to `[]`; maximum `9` images. **Role and numbering:** - Every image is used as `reference_image` - The first item is `Image 1`, the second is `Image 2`, and so on **Image requirements:** - Formats: JPG, JPEG, PNG, WEBP, HEIC, HEIF - File size: no more than `30MB` each - Width and height: each from `256` to `5760` px - Aspect ratio (width/height): `0.4`–`2.5` - URLs must use HTTP(S) and be directly accessible by the service - The complete JSON request body must not exceed `64MB`; Base64 and `mm_file://` inputs are not accepted **Combination rules:** - Provide at least `1` reference image or `1` reference video - Supplying only `audio_urls` returns a parameter error default: [] maxItems: 9 items: type: string format: uri example: - >- https://cdn.hailuoai.com/prod/hailuo_demo/testsets/H3_AA_I2VA/gallery/sr_v17_variants_seed42_43_20260724/inputs/4a3a90bf9100_KDmcbkhzYo5sjjxr9FqcVmWVnzb.png video_urls: type: array description: >- **Applicable models:** - Only `minimax-h3-reference-to-video` - Text-to-video and image-to-video do not support this parameter Array of HTTP(S) reference-video URLs. Defaults to `[]`; maximum `3` videos. **Role and numbering:** - Every video is used as `reference_video` - The first item is `Video 1`, the second is `Video 2`, and so on **Video requirements:** - Containers: MP4 (`.mp4`), MOV (`.mov`) - Video codecs: H.264/AVC, H.265/HEVC - Embedded audio codecs: AAC, MP3 - File size: no more than `50MB` each - Duration: `2`–`15` seconds per clip; total reference-video duration no more than `15` seconds - Width and height: each from `256` to `5760` px - Aspect ratio (width/height): `0.4`–`2.5` - Frame rate: `23.976`–`60` FPS - URLs must use HTTP(S) and be directly accessible by the service - The complete JSON request body must not exceed `64MB`; Base64 and `mm_file://` inputs are not accepted **Billing:** - Reference-video input duration is billable **Combination rules:** - Provide at least `1` reference image or `1` reference video - Supplying only `audio_urls` returns a parameter error default: [] maxItems: 3 items: type: string format: uri example: - >- https://cdn.hailuoai.com/prod/hailuo_demo/testsets/h3_promo_eval_ref2va/gallery/sr_v2p26_trio_seed42_20260724/inputs/297573323635_00_%E8%A7%86%E9%A2%911_YnyRbxEwio_video_20260525_163755_1927e9d3.mp4 audio_urls: type: array description: >- **Applicable models:** - Only `minimax-h3-reference-to-video` - Text-to-video and image-to-video do not support this parameter Array of HTTP(S) reference-audio URLs. Defaults to `[]`; maximum `3` clips. **Role and numbering:** - Every audio clip is used as `reference_audio` - The first item is `Audio 1`, the second is `Audio 2`, and so on **Audio requirements:** - Formats: WAV, MP3 - File size: no more than `15MB` each - Duration: `2`–`15` seconds per clip; total reference-audio duration no more than `15` seconds - URLs must use HTTP(S) and be directly accessible by the service - The complete JSON request body must not exceed `64MB`; Base64 and `mm_file://` inputs are not accepted **Combination rules:** - Reference audio cannot be used by itself - When using `audio_urls`, also provide at least `1` reference image or `1` reference video default: [] maxItems: 3 items: type: string format: uri example: - >- https://cdn.hailuoai.com/prod/hailuo_demo/testsets/h3_promo_eval_ref2va/gallery/sr_v2p26_trio_seed42_20260724/inputs/f463d523c5ce_01_%E9%9F%B3%E9%A2%911_RSLcbpzJPo_6%E6%9C%885%E6%97%A5(1).mp3 duration: type: integer description: |- Output video duration in seconds. Defaults to `5` seconds. **Value restrictions:** - Only integers from `5` through `15`, inclusive, are supported - Decimals, numeric strings, `auto`, and `-1` are not supported - Output duration directly affects billing **Applicable models:** - All 3 Minimax H3 models default: 5 minimum: 5 maximum: 15 example: 5 quality: type: string description: >- Output video resolution. Defaults to `2k`. **Available value:** - `2k`: the only resolution currently supported **Notes:** - `768p` is not yet available and returns a parameter error - Output bitrate, frame rate, video codec, and audio codec are selected by the platform and are not configurable **Applicable models:** - All 3 Minimax H3 models enum: - 2k default: 2k example: 2k aspect_ratio: type: string description: >- Output video aspect ratio. Defaults to `adaptive`. **Applicable models:** - Supported by `minimax-h3-text-to-video` - Supported by `minimax-h3-reference-to-video` - **Not supported by `minimax-h3-image-to-video`; do not send this parameter in image-to-video requests** **Available values:** - `adaptive`: The model selects an appropriate aspect ratio from the prompt or reference assets - `21:9`: Ultrawide - `16:9`: Landscape - `4:3`: Standard landscape - `1:1`: Square - `3:4`: Standard portrait - `9:16`: Portrait enum: - adaptive - '21:9' - '16:9' - '4:3' - '1:1' - '3:4' - '9:16' default: adaptive example: adaptive callback_url: type: string description: >- HTTPS callback URL for task completion **Callback timing:** - Triggered when the task is completed or failed - Sent after billing confirmation is complete **Security restrictions:** - Only HTTPS protocol is supported - Callbacks to private IP addresses are prohibited (127.0.0.1, 10.x.x.x, 172.16-31.x.x, 192.168.x.x, etc.) - URL length must not exceed `2048` characters **Callback mechanism:** - Timeout: `10` seconds - Up to `3` retries after failure (at `1`/`2`/`4` seconds after failure respectively) - Callback response body format is consistent with the task query endpoint response format - A 2xx status code is considered successful; other status codes trigger retries **Applicable models:** - All 3 Minimax H3 models format: uri example: https://your-domain.com/webhooks/video-task-completed pattern: ^https:// additionalProperties: false VideoGenerationResponse: type: object properties: created: type: integer description: Task creation timestamp example: 1761313744 id: type: string description: Task ID example: task-unified-1774857405-abc123 model: type: string description: Actual model name used example: minimax-h3-text-to-video object: type: string enum: - video.generation.task description: Specific type of the task progress: type: integer description: Task progress percentage (0-100) minimum: 0 maximum: 100 example: 0 status: type: string description: Task status enum: - pending - processing - completed - failed example: pending task_info: $ref: '#/components/schemas/VideoTaskInfo' description: Video task details type: type: string enum: - text - image - audio - video description: Output type of the task example: video usage: $ref: '#/components/schemas/VideoUsage' description: Usage and billing information ErrorResponse: type: object properties: error: type: object properties: code: type: string description: Error code identifier message: type: string description: Error description message type: type: string description: Error type VideoTaskInfo: type: object properties: can_cancel: type: boolean description: >- Whether the task can be canceled. Minimax H3 tasks cannot be canceled; always `false`. example: false enum: - false default: false estimated_time: type: integer description: Estimated completion time (seconds) minimum: 0 example: 165 video_duration: type: integer description: Video duration (seconds) example: 8 VideoUsage: type: object description: Usage and billing information properties: billing_rule: type: string description: Billing rule enum: - per_call - per_token - per_second example: per_second credits_reserved: type: number description: Estimated credits consumed minimum: 0 example: 50 user_group: type: string description: User group category example: default securitySchemes: bearerAuth: type: http scheme: bearer description: >- ##All endpoints require Bearer Token authentication## **Get API Key:** Visit the [API Key Management Page](https://evolink.ai/dashboard/keys) to obtain your API Key **Add to request header:** ``` Authorization: Bearer YOUR_API_KEY ``` ````