Fattly

fattly_generate_ad_video

Ad Studio VIDEO ad (premium, ~150 credits): a real-looking creator presents your product on camera with a real voice — the full site flow. Takes a few minutes; the tool waits ~2 min and then returns an id to check with fattly_video_status.

Input Schema

Name	Required	Description
`mode`	Yes	product = creator holds your product (needs productImageUrl). service = creator talks to camera, no product in frame. handsdemo = POV hands + product, NO face on screen, voice-over off camera (this is the site mode named: no avatar; needs productImageUrl). unboxing = silent ASMR unboxing, hands only, no speech — `script` is ignored, steer the shot with `prompt` instead.
`locale`	No	Spoken language (default en). EN uses native Kling audio; other languages use Gemini Omni 1.1, which speaks the script itself.
`prompt`	No	The idea / how the shot should look (room, lighting, what the creator does). Not spoken — it directs the scene. Also the source we write the script from when `script` is empty.
`script`	No	What the creator SAYS on camera, word for word. One clip fits about 20–25 spoken words (numbers and prices count as they are read aloud); a longer script is rejected with a message saying how many words to cut — nothing is charged. Optional: with no script we write one from `prompt` for free. Ignored in unboxing mode (that ad has no speech).
`actorId`	No	Avatar you generated with fattly_create_avatar — the SAME creator presents the product.
`consent`	No	REQUIRED (true) when you pass avatarUrl (your own creator photo). Must be true. By setting it you confirm that you have the rights to, and the consent of, every person who is visible or audible in the materials you provide.
`setting`	No	Scene id from fattly_list_ad_presets.
`voiceId`	No	Only for handsdemo mode with a single clip: a voice you saved earlier (savedVoiceId from fattly_clone_voice) reads the script as the voice-over instead of the model's voice (+ the saved-voice price). Ignored in other modes.
`avatarId`	No	Creator from the built-in roster (see fattly_list_ad_presets).
`avatarUrl`	No	Your own creator photo as a fal URL. Using a photo of a real person requires consent: true.
`unbranded`	No	Keep the product free of invented branding.
`templateId`	No	Ad preset id — must be a non-graphic preset (see fattly_list_ad_presets).
`aspectRatio`	No	Video shape: 9:16 vertical (default, TikTok/Reels) or 16:9 landscape.
`productImageUrl`	No	Product photo as a fal URL — REQUIRED for product mode. Use fattly_upload_image.

Schema Changelog

Changes observed during successful MCP inspections.

Changed2 schema fields changedOct 22, 2026

removedInput schema / properties / voice

Removed value: -{
-  "description": "Voice name for non-EN locales.",
-  "type": "string"
-}

addedInput schema / properties / voiceId

Added value: +{
+  "description": "Only for handsdemo mode with a single clip: a voice you saved earlier (savedVoiceId from fattly_clone_voice) reads the script as the voice-over instead of the model's voice (+ the saved-voice price). Ignored in other modes.",
+  "type": "string"
+}

Changed1 schema field changedOct 14, 2026

changedInput schema / properties / script / description

Previous value: -"What the creator SAYS on camera, word for word. Keep it short — a few seconds of speech. Optional: with no script we write one from `prompt` for free. Ignored in unboxing mode (that ad has no speech)."New value: +"What the creator SAYS on camera, word for word. One clip fits about 20–25 spoken words (numbers and prices count as they are read aloud); a longer script is rejected with a message saying how many words to cut — nothing is charged. Optional: with no script we write one from `prompt` for free. Ignored in unboxing mode (that ad has no speech)."

Changed1 schema field changedOct 13, 2026

changedInput schema / properties / locale / description

Previous value: -"Spoken language (default en). EN uses native Kling audio; others use Veo/TTS."New value: +"Spoken language (default en). EN uses native Kling audio; other languages use Gemini Omni 1.1, which speaks the script itself."

Changed2 schema fields changedSep 27, 2026

changedInput schema / properties / avatarUrl / description

Previous value: -"Your own creator photo as a fal URL."New value: +"Your own creator photo as a fal URL. Using a photo of a real person requires consent: true."

addedInput schema / properties / consent

Added value: +{
+  "description": "REQUIRED (true) when you pass avatarUrl (your own creator photo). Must be true. By setting it you confirm that you have the rights to, and the consent of, every person who is visible or audible in the materials you provide.",
+  "type": "boolean"
+}

Changed8 schema fields changedSep 23, 2026

addedInput schema / properties / aspectRatio

Added value: +{
+  "description": "Video shape: 9:16 vertical (default, TikTok/Reels) or 16:9 landscape.",
+  "enum": [
+    "9:16",
+    "16:9"
+  ],
+  "type": "string"
+}

changedInput schema / properties / locale / description

Previous value: -"Spoken language (default en). EN uses native Kling audio; others use TTS + avatar."New value: +"Spoken language (default en). EN uses native Kling audio; others use Veo/TTS."

changedInput schema / properties / locale / enum

Previous value: -[
-  "en",
-  "pl",
-  "de",
-  "es"
-]New value: +[
+  "en",
+  "pl",
+  "de",
+  "es",
+  "fr"
+]

changedInput schema / properties / mode / description

Previous value: -"product = creator holds your product (needs productImageUrl). service = creator talks to camera, no product in frame."New value: +"product = creator holds your product (needs productImageUrl). service = creator talks to camera, no product in frame. handsdemo = POV hands + product, NO face on screen, voice-over off camera (this is the site mode named: no avatar; needs productImageUrl). unboxing = silent ASMR unboxing, hands only, no speech — `script` is ignored, steer the shot with `prompt` instead."

changedInput schema / properties / mode / enum

Previous value: -[
-  "product",
-  "service"
-]New value: +[
+  "product",
+  "service",
+  "handsdemo",
+  "unboxing"
+]

addedInput schema / properties / prompt

Added value: +{
+  "description": "The idea / how the shot should look (room, lighting, what the creator does). Not spoken — it directs the scene. Also the source we write the script from when `script` is empty.",
+  "type": "string"
+}

changedInput schema / properties / script / description

Previous value: -"What the creator SAYS on camera. Keep it short — a few seconds of speech."New value: +"What the creator SAYS on camera, word for word. Keep it short — a few seconds of speech. Optional: with no script we write one from `prompt` for free. Ignored in unboxing mode (that ad has no speech)."

changedInput schema / required

Previous value: -[
-  "mode",
-  "script"
-]New value: +[
+  "mode"
+]

First observedSep 15, 2026

TDQS

A3.8/5.0

Behavior4/5

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

Annotations only declare it as a non-readonly, non-idempotent, non-destructive mutation. The description adds genuinely useful context the annotations lack: a ~150 credit cost, a multi-minute runtime, a ~2 minute internal wait, and an async id returned for polling via fattly_video_status.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness4/5

Is the description appropriately sized, front-loaded, and free of redundancy?

Two dense sentences, cost and runtime front-loaded, ending with the actionable next step. The phrase 'the full site flow' is vague filler that doesn't earn its place, keeping it from a 5.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness5/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

For a 14-parameter tool with full schema coverage and no output schema, the description supplies exactly the missing operational layer: cost, latency, the async id return, and the status-check sibling. Nothing needed to invoke or follow up is absent.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters3/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema description coverage is 100% and the per-parameter docs are unusually rich (mode semantics, script length limits, consent rules). The description prose adds no parameter-level meaning, so the schema does all the work — baseline 3 is appropriate.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose4/5

Does the description clearly state what the tool does and how it differs from similar tools?

Names a specific verb+resource: generates a 'VIDEO ad' where 'a real-looking creator presents your product on camera with a real voice'. It implies a contrast with the sibling fattly_generate_ad but never names it, leaving the sibling differentiation implicit rather than stated.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines3/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

Usage is only implied — the agent can infer this is the premium video path versus cheaper alternatives, and the description explicitly routes follow-up to fattly_video_status. But it gives no explicit when-to-use/when-not guidance versus fattly_generate_ad or fattly_generate_video.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.

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fattly_generate_ad_video

Input Schema

Schema Changelog

TDQS

Glama MCP Gateway

Resources