> ## Documentation Index > Fetch the complete documentation index at: https://docs.mosaic.so/llms.txt > Use this file to discover all available pages before exploring further. # 1. AI Avatar > Create reusable AI presenters and generate talking-head videos from scripts. AI Avatar creates a reusable presenter from a short reference clip or image/voice pair, then generates talking-head videos from a script. It is best for founder updates, explainers, UGC ads, training videos, and repeatable spokesperson content. ## How It Works The AI Avatar flow has two parts: * **Create an avatar:** provide a 4-15 second source video, or provide an image plus a 4-15 second voice reference. Mosaic processes this into reusable avatar references. * **Generate a video:** select the avatar profile, write the script, choose the model and take style, then run the agent. AI Avatar ## Avatar Profiles Avatars live in your workspace library and can be used from the editor or API. Mosaic prepares the reference video, reference image, and voice audio during processing. Recommended source video: * 4-15 seconds long * Exactly one person on screen * Clear face, direct-to-camera framing * Natural speech with visible mouth movement from that person * Clean single-speaker audio from that person; avoid background speakers, music, heavy noise, or dubbing * Minimal cuts, overlays, or visual effects If you use an image plus voice reference instead of a source video, the image should show the same single person you want to generate, and the voice reference should contain only that person's clear speech. ## Single Take vs Multitake **Single take** asks the model for one continuous delivery. Use it for short scripts where a natural uninterrupted performance matters most. **Multitake** lets Mosaic split longer scripts into sentence-complete chunks, render multiple takes, normalize them, and stitch the final output. Use it for longer scripts, retries, or workflows where reliability matters more than one uninterrupted provider clip. Seedance 2 and Seedance 2 Fast support both modes in Mosaic. In multitake mode, Mosaic still preserves the avatar identity and voice while chunking the script behind the scenes. ## Model Options Seedance 2 and Seedance 2 Fast are the recommended AI Avatar models. They are Mosaic's most cost-effective and life-like avatar generation options, and they support both single take and multitake generation with avatars from your library. | Model | Best For | Notes | | ------------------ | -------------------------------------------- | ---------------------------------------------------------------------------------- | | `seedance-2-fast` | Recommended fast avatar generation | Most cost-effective option. Fast provider output is upscaled to 1080p when needed. | | `seedance-2` | Recommended high-quality avatar generation | Most life-like option. Supports 16:9 and 9:16. | | `avatar-v4` | Legacy Longcat 1 single-take avatars | Requires a voice reference or avatar profile. | | `fabric-1` | Legacy lip-sync style single-take generation | Can use an uploaded voiceover. | | `kling-2.6-pro` | Legacy multitake avatar generation | Supports product and character references. | | `kling-3-standard` | Legacy multitake avatar generation | Shown as Kling 3 in the editor. | | `kling-3-pro` | Legacy multitake avatar generation | Higher-cost legacy Kling option. | ## API Workflow 1. Create an avatar with `POST /avatar-profiles/create`. 2. Create an agent with `POST /agent/create`, then add an AI Avatar node with `POST /agent/{agent_id}/update`. 3. Run the agent with `POST /agent/{agent_id}/run` and no video inputs. Avatar processing starts automatically when you create the avatar. You can use the avatar ID in an AI Avatar tile immediately; if the avatar is still processing, the run waits for it to become ready. If the avatar's `processing_status` is `failed`, create a new avatar before using it. Create an avatar: ```bash theme={null} curl -X POST "https://api.mosaic.so/avatar-profiles/create" \ -H "Authorization: Bearer mk_your_api_key" \ -H "Content-Type: application/json" \ -d '{ "name": "Founder Avatar", "sources": { "video_url": "https://example.com/founder-reference.mp4" } }' ``` Create an agent shell: ```bash theme={null} curl -X POST "https://api.mosaic.so/agent/create" \ -H "Authorization: Bearer mk_your_api_key" \ -H "Content-Type: application/json" \ -d '{ "name": "Seedance Avatar Generator", "visibility": "private" }' ``` Add an AI Avatar node: ```bash theme={null} curl -X POST "https://api.mosaic.so/agent/AGENT_ID/update" \ -H "Authorization: Bearer mk_your_api_key" \ -H "Content-Type: application/json" \ -d '{ "operations": [ { "op": "create_node", "node_type_id": "b3b4c9e2-2a47-4fa9-8ce8-0c1fa1d7b6ef", "params_used": { "avatar_profile_id": "AVATAR_PROFILE_ID", "video_model": "seedance-2-fast", "single_take": false, "aspect_ratio": "9:16", "script": "Here is the exact script the avatar should say." } } ] }' ``` Run the AI Avatar agent: ```bash theme={null} curl -X POST "https://api.mosaic.so/agent/AGENT_ID/run" \ -H "Authorization: Bearer mk_your_api_key" \ -H "Content-Type: application/json" \ -d '{ "callback_url": "https://your-webhook.com/mosaic" }' ``` Use `video_model: "seedance-2"` for the higher-quality Seedance 2 path. Set `single_take: true` for one continuous delivery, or `false` for multitake chunking. *** ## API Info * **Node ID:** `b3b4c9e2-2a47-4fa9-8ce8-0c1fa1d7b6ef` ### Node params | Param | Type | Required | Default | Notes | | --------------------------- | -------------------------------------------------------------------------------------------------------------------------- | ----------- | ------------------- | ----------------------------------------------------------------------------- | | `brief` | `string` | Yes | `""` | High-level intent/context (validated, \~1-1000 chars). | | `script` | `string` | Yes | `""` | Spoken script. | | `video_model` | `"seedance-2-fast" \| "seedance-2" \| "kling-2.6-pro" \| "kling-3-standard" \| "kling-3-pro" \| "fabric-1" \| "avatar-v4"` | No | `"seedance-2-fast"` | Generation model choice. | | `single_take` | `boolean` | No | `true` | `true` for one continuous delivery; `false` for multitake chunking/stitching. | | `aspect_ratio` | `"9:16" \| "16:9" \| "auto"` | No | `"9:16"` | Output framing mode. | | `avatar_profile_id` | `string` (UUID) | Conditional | unset | Reusable avatar. Required for Seedance 2 models. | | `creation_mode` | `"manual" \| "video_reference"` | No | `"manual"` | Avatar generation flow selection. | | `reference_video_id` | `string` (UUID) | Conditional | unset | Used when `creation_mode="video_reference"`. | | `reference_change_request` | `string` | No | `""` | Optional instructions when using video-reference mode. | | `product_image_id` | `string` (UUID) | No | unset | Product reference image. | | `character_image_id` | `string` (UUID) | No | unset | Avatar/character image override. | | `voice_reference_id` | `string` (UUID) | No | unset | Voice reference asset ID for cloning. | | `voice_reference_type` | `"audio" \| "video"` | Conditional | unset | Required when `voice_reference_id` is provided. | | `voiceover_id` | `string` (UUID) | Conditional | unset | Optional voiceover upload for Fabric 1 lip-sync path. | | `voiceover_type` | `"audio" \| "video"` | Conditional | unset | Required when `voiceover_id` is provided. | | `elevenlabs_model_id` | `string` | No | unset | Explicit ElevenLabs model override. | | `elevenlabs_voice_settings` | `{stability?:number,similarity_boost?:number,style?:number,use_speaker_boost?:boolean,speed?:number}` | No | unset | Fine-grained TTS tuning object. | | `voice_dictionary` | `Array<{word:string,audio_id:string,enabled:boolean}>` | No | `[]` | Up to three pronunciation references for Seedance 2. | ### Parameter groups * **Core generation:** `brief`, `script`, `video_model`, `single_take`, `aspect_ratio` * **Avatar library:** `avatar_profile_id` * **Creation flow:** `creation_mode`, `reference_video_id`, `reference_change_request` * **Visual references:** `product_image_id`, `character_image_id` * **Voice references:** `voice_reference_id`, `voice_reference_type`, `voiceover_id`, `voiceover_type` * **Voice tuning:** `elevenlabs_model_id`, `elevenlabs_voice_settings`, `voice_dictionary` ### Example ```json theme={null} { "avatar_profile_id": "aaaaaaaa-aaaa-aaaa-aaaa-aaaaaaaaaaaa", "script": "We built this to help teams publish polished videos in minutes.", "aspect_ratio": "9:16", "video_model": "seedance-2-fast", "single_take": false } ```