> ## Documentation Index > Fetch the complete documentation index at: https://testweb2-docs-openapi.test765.com/llms.txt > Use this file to discover all available pages before exploring further. > ## Agent Instructions > Five API is a video generation REST API. Base URL: https://api.fiveapi.ai. Authenticate with the header Authorization: Bearer ; read the key from the FIVEAPI_API_KEY environment variable and never hard-code it. > Every generation is an asynchronous task: POST /v1/{brand}/{version}/{task} returns a queued task, then poll GET /v1/tasks/{task_id} or receive a signed webhook, and download output.video.url before expires_at (7 days). > The OpenAPI spec is at https://docs.fiveapi.ai/api-reference/openapi.yaml. An installable agent skill: npx skills add https://docs.fiveapi.ai # Input files > How to pass images, videos and audio to Five API: public HTTPS URLs, the URL policy and the limits of each model. Five API takes input files as **URLs**. There is no upload endpoint: host the file somewhere public, for example in your own object storage, and pass its HTTPS URL in the request. | Field | Used by | What it points to | | - | - | - | | `image_url` | image to video | The image to animate | | `reference_images`, `reference_videos`, `reference_audios` | reference to video | Arrays of asset URLs | | `video_url` | video extend | The clip to continue | ## URL policy Five API checks every input URL **when you create the task**, before any credit is held. A URL that breaks a rule answers `400 url_not_allowed` with the field in `param`. * **HTTPS only.** `http://` URLs are rejected. * **Public host.** The host name must resolve, through public DNS, to a public IP address. Private, loopback, link-local, carrier-grade NAT, cloud metadata and other reserved ranges are rejected. * **Answers `HEAD`.** Five API sends a `HEAD` request to the URL. It must answer `2xx`, after at most 3 redirects; each redirect target is checked again. * **Within the size limit.** The `Content-Length` must not exceed the limit of the model (see below). The same host rules apply to `webhook_url`. > [!TIP] > > Presigned URLs from S3, Google Cloud Storage, Azure Blob Storage, Cloudflare R2 and similar services work well. Keep them valid for at least an hour: a task downloads its input files after it is created, while it is queued. ## Limits per model | Model | Input | Formats and limits | | - | - | - | | Video Fast 1.0, image to video | `image_url` | JPG, PNG or WebP; shorter side at least 300 px; aspect ratio between 0.4 and 2.5; at most 30 MB | | Wan 3.0 Spark and Prime Spark, image to video | `image_url` | JPG, PNG or WebP; 360–2,000 px per side; at most 20 MB | | Video Fast 1.0, reference to video | `reference_images` | Up to 9 images: JPG, PNG or WebP; 256–5,760 px; at most 30 MB each | | | `reference_videos` | Up to 3 clips: 2–15 seconds and at most 50 MB each | | | `reference_audios` | Up to 3 files: at most 15 MB each; send them together with an image or a video | | Wan 3.0 Spark, reference to video | `reference_images` | Up to 10 images: JPG, PNG or WebP; at most 20 MB each | | | `reference_videos` | Up to 5 clips: at most 100 MB each | | | `reference_audios` | Up to 5 files: at most 15 MB each | | Video Fast Extend 1.1 | `video_url` | MP4 or MOV; 360–2,000 px per side; 2–30 seconds after the optional window; at most 500 MB | `GET /v1/models/{brand}/{version}/{task}` returns each model's limits in `input_schema`, including `x-max-input-bytes`, the largest accepted file. ## When an input fails later The URL check at creation can't see everything inside a file. If a file turns out to be unusable during processing, the task fails and its credits are released: * `input_fetch_failed` (retryable): the file could not be downloaded or processed, for example because a presigned URL expired. * `input_invalid` (not retryable): the file was downloaded but its format, dimensions or length do not fit the model. ## Troubleshooting `url_not_allowed` | Cause | Fix | | - | - | | The URL uses `http` | Serve it over `https` | | The host resolves to a private or reserved address | Use a publicly hosted file; internal hosts and DNS overrides are not reachable | | The server doesn't answer `HEAD`, or answers without `Content-Length` | Host the file on object storage or a CDN that supports `HEAD` | | More than 3 redirects | Pass the final URL | | The file is larger than the model's limit | Compress or resize it, or choose a model with a higher limit | This documentation is built and hosted on [Mintlify](https://mintlify.com), a developer documentation platform.