> ## 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 # Video Fast Extend 1.1 — video extend > Continue an existing clip with **Video Fast Extend 1.1**, with matched audio when `generate_audio` is true. 480p, 720p or 1080p. `duration` is the number of seconds **added** after the clip (3–30). The clip, after the optional `start_time` / `end_time` window (send both or neither), must be 2–30 seconds long, and clip plus added seconds may not exceed 30 seconds. The result is the clip followed by the continuation, so `output.video.duration` is at least `duration`. The clip must be a public HTTPS URL of an MP4 or MOV file, 360–2,000 px per side, at most 500 MB. Guide: [Video extend](/guides/video-extend). ## OpenAPI ````yaml /api-reference/openapi.yaml post /v1/video-fast/v1.1/video-extend openapi: 3.1.0 info: title: Five API version: 1.0.0 summary: Generate AI videos from text, images, reference assets and clips. description: > The Five API turns a text prompt, an image, a set of reference assets or a video clip into a short video. Every generation is an asynchronous **task**: `POST /v1/{brand}/{version}/{task}` returns a `queued` task at once, and the result arrives by webhook or by polling `GET /v1/tasks/{task_id}`. * Base URL: `https://api.fiveapi.ai` * Authentication: `Authorization: Bearer ` (or the `x-api-key` header) * JSON in and out, `snake_case` fields, UTF-8, ISO 8601 UTC timestamps * Every response carries `X-Request-Id`; error bodies repeat it as `error.request_id` contact: name: Five API support email: support@fiveapi.ai url: https://docs.fiveapi.ai servers: - url: https://api.fiveapi.ai description: Production security: - bearerAuth: [] tags: - name: Video Fast 1.0 description: Fast, low-cost generation at 480p or 768p. - name: Wan 3.0 Spark description: Native 30-second video with richer detail and synchronized audio. - name: Wan 3.0 Prime Spark description: Wan 3.0 quality at full 30 seconds, noticeably faster. - name: Video Fast Extend 1.1 description: Continue an existing clip with matched audio. - name: Tasks description: Read, list and cancel generation tasks. - name: Models description: The model catalogue and each model's input schema. - name: Account description: Balance, plan limits and daily usage. paths: /v1/video-fast/v1.1/video-extend: post: tags: - Video Fast Extend 1.1 summary: Video Fast Extend 1.1 — video extend description: > Continue an existing clip with **Video Fast Extend 1.1**, with matched audio when `generate_audio` is true. 480p, 720p or 1080p. `duration` is the number of seconds **added** after the clip (3–30). The clip, after the optional `start_time` / `end_time` window (send both or neither), must be 2–30 seconds long, and clip plus added seconds may not exceed 30 seconds. The result is the clip followed by the continuation, so `output.video.duration` is at least `duration`. The clip must be a public HTTPS URL of an MP4 or MOV file, 360–2,000 px per side, at most 500 MB. Guide: [Video extend](/guides/video-extend). operationId: videoFastExtend11VideoExtend parameters: - $ref: '#/components/parameters/IdempotencyKey' requestBody: required: true content: application/json: schema: $ref: '#/components/schemas/VideoExtendRequest' examples: window: summary: Add 5 seconds after the first 8 seconds of a clip value: video_url: https://assets.example.com/inputs/clip.mp4 prompt: the camera keeps panning right across the skyline duration: 5 resolution: 480p start_time: 0 end_time: 8 responses: '200': description: The task was accepted and queued. headers: X-Request-Id: $ref: '#/components/headers/X-Request-Id' Idempotent-Replayed: $ref: '#/components/headers/Idempotent-Replayed' content: application/json: schema: $ref: '#/components/schemas/Task' example: id: task_01J9XG8H9J0K1L2M3N4P5Q6R7S object: task model: video-fast/v1.1/video-extend task: video-extend status: queued input: video_url: https://assets.example.com/inputs/clip.mp4 prompt: the camera keeps panning right across the skyline duration: 5 resolution: 480p start_time: 0 end_time: 8 error: null credits: estimated: 68 created_at: '2026-10-23T08:02:00.000Z' '400': $ref: '#/components/responses/BadRequest' '401': $ref: '#/components/responses/Unauthorized' '402': $ref: '#/components/responses/PaymentRequired' '403': $ref: '#/components/responses/Forbidden' '409': $ref: '#/components/responses/Conflict' '429': $ref: '#/components/responses/TooManyRequests' '500': $ref: '#/components/responses/InternalError' '503': $ref: '#/components/responses/ServiceUnavailable' components: parameters: IdempotencyKey: name: Idempotency-Key in: header required: false description: > Optional key that makes the request safe to retry: any string up to 128 characters, unique per account, kept for 24 hours. The same key with the same body replays the first answer (`Idempotent-Replayed: true`) instead of creating a second task. See [Idempotency](/concepts/idempotency). schema: type: string maxLength: 128 examples: - order-8812-attempt-1 schemas: VideoExtendRequest: type: object title: Video Fast Extend 1.1 request required: - video_url - prompt - duration - resolution properties: video_url: type: string format: uri description: >- Public HTTPS URL of the MP4 or MOV clip to continue, 360–2,000 px per side, at most 500 MB. The clip (after the optional window) must be 2–30 seconds long. examples: - https://assets.example.com/inputs/clip.mp4 prompt: type: string maxLength: 2000 description: How the video continues after the clip. examples: - the camera keeps panning right across the skyline start_time: type: number minimum: 0 description: >- Start of the window of the clip to continue from, in seconds. Send `start_time` and `end_time` together, or neither. examples: - 0 end_time: type: number description: End of the window, in seconds. Must be greater than `start_time`. examples: - 8 duration: type: integer minimum: 3 maximum: 30 description: >- Seconds to add after the clip. Clip plus added seconds may not exceed 30 seconds. examples: - 5 resolution: type: string enum: - 480p - 720p - 1080p description: Output resolution. examples: - 480p generate_audio: $ref: '#/components/schemas/GenerateAudio' prompt_expansion: $ref: '#/components/schemas/PromptExpansion' webhook_url: $ref: '#/components/schemas/WebhookUrl' metadata: $ref: '#/components/schemas/Metadata' Task: type: object description: >- A generation task. `error` is always present (`null` unless the task failed); other empty members are omitted. required: - id - object - model - task - status - input - error - credits - created_at properties: id: type: string description: Task id, `task_` followed by 26 characters. examples: - task_01J9X7Z0K7Q8W3F2P1N6M5V4R3 object: type: string const: task model: type: string description: The model id the task was created with. examples: - wan/v3.0-spark/image-to-video task: type: string enum: - text-to-video - image-to-video - reference-to-video - video-extend description: The task type, the last segment of the model id. status: $ref: '#/components/schemas/TaskStatus' input: type: object additionalProperties: true description: The accepted request body, without `webhook_url` and `metadata`. output: $ref: '#/components/schemas/TaskOutput' error: description: Why the task failed. `null` unless `status` is `failed`. oneOf: - $ref: '#/components/schemas/TaskError' - type: 'null' credits: $ref: '#/components/schemas/Credits' queue: $ref: '#/components/schemas/Queue' webhook_url: type: string format: uri description: The webhook URL sent with the task. metadata: type: object additionalProperties: true description: The metadata sent with the task. created_at: type: string format: date-time description: When the task was created. started_at: type: string format: date-time description: When generation started. completed_at: type: string format: date-time description: When the task reached `completed`, `failed` or `cancelled`. expires_at: type: string format: date-time description: When the output is removed, 7 days after completion. GenerateAudio: type: boolean default: false description: Generate synchronized audio together with the video. PromptExpansion: type: string enum: - none - basic - advanced default: advanced description: >- How much the prompt is rewritten before generation: `none` keeps your text, `basic` polishes it, `advanced` expands it into a detailed shot description. The final text is returned as `output.actual_prompt`. WebhookUrl: type: string format: uri description: >- Public HTTPS URL that receives this task's events. Overrides your account's default webhook endpoint. examples: - https://hooks.example.com/fiveapi Metadata: type: object additionalProperties: true description: >- Your own JSON, up to 4,096 bytes when serialized. Returned unchanged on the task and in every webhook. examples: - order_id: ord_8812 TaskStatus: type: string enum: - queued - processing - completed - failed - cancelled description: >- `queued` → `processing` → one of the terminal states `completed`, `failed`, `cancelled`. TaskOutput: type: object description: The result. Present on `completed` tasks until `expires_at`. properties: video: $ref: '#/components/schemas/Video' actual_prompt: type: string description: The prompt after expansion, when it was rewritten. seed: type: integer format: int64 description: The seed used, when the model reports it. TaskError: type: object description: Why a task failed. required: - code - message - retryable properties: code: type: string enum: - input_fetch_failed - input_invalid - content_moderation_rejected - generation_failed - timeout - service_unavailable description: Stable failure code. See [Errors](/concepts/errors#task-failures). message: type: string description: Human-readable detail. It may change; branch on `code`. retryable: type: boolean description: True when submitting the same request again may succeed. reason: type: string enum: - ip - audio_copyright - public_figure description: 'For `content_moderation_rejected`: the category, when classified.' Credits: type: object required: - estimated properties: estimated: type: integer format: int64 description: Credits held when the task was accepted. examples: - 60 charged: type: integer format: int64 description: >- Credits charged. Set when the task completes; absent on failed and cancelled tasks, whose hold was released. examples: - 60 Queue: type: object description: Present while the task is `queued`. properties: position: type: integer description: Position in the model's queue; lower starts sooner. examples: - 3 Error: type: object required: - error properties: error: type: object required: - type - code - message - request_id properties: type: type: string enum: - invalid_request_error - authentication_error - billing_error - permission_error - not_found_error - conflict_error - rate_limit_error - api_error description: The error category. code: type: string description: >- Stable machine-readable code. Branch on this, never on `message`. examples: - insufficient_credits message: type: string description: Human-readable detail. It may change. param: type: string description: The request field at fault, when there is one. request_id: type: string description: Same as the `X-Request-Id` header. details: type: object additionalProperties: true description: >- Extra members for some codes, for example `required` and `available` on `insufficient_credits`. Video: type: object properties: url: type: string format: uri description: Download URL of the MP4, valid until `expires_at`. examples: - >- https://openassets.fiveapi.ai/x2v/results/551fe9fa/openapi_1793171336.mp4 content_type: type: string examples: - video/mp4 file_size: type: integer format: int64 description: Size in bytes. width: type: integer description: Width in pixels. height: type: integer description: Height in pixels. duration: type: number description: Length in seconds. fps: type: integer description: Frames per second. cover_url: type: string format: uri description: First-frame image (JPG), when available. headers: X-Request-Id: description: Id of this request (`req_...`). Quote it when you contact support. schema: type: string examples: - req_01M5KPY92Y148QP01G532MM3BH Idempotent-Replayed: description: '`true` when the response was replayed for a repeated `Idempotency-Key`.' schema: type: string examples: - 'true' Retry-After: description: Seconds to wait before retrying. schema: type: integer examples: - 10 X-RateLimit-Limit: description: >- Requests per minute allowed for your account (or the key's lower ceiling). schema: type: integer examples: - 300 X-RateLimit-Remaining: description: Requests left in the current minute. schema: type: integer examples: - 287 X-RateLimit-Reset: description: Unix time in seconds when the minute window resets. schema: type: integer format: int64 examples: - 1792736640 responses: BadRequest: description: > The request is malformed or breaks the model's rules: `invalid_json`, `missing_parameter`, `invalid_parameter`, `unsupported_model`, `url_not_allowed` or `idempotency_key_reused`. Nothing was charged. headers: X-Request-Id: $ref: '#/components/headers/X-Request-Id' content: application/json: schema: $ref: '#/components/schemas/Error' examples: missing_parameter: summary: A required field is missing value: error: type: invalid_request_error code: missing_parameter message: 'missing required parameter: duration' param: duration request_id: req_01M5KN36M1JPANPMDW0HEWMMB0 invalid_parameter: summary: A resolution and duration the model does not offer value: error: type: invalid_request_error code: invalid_parameter message: duration 20 s at 768p is not available on this model param: duration request_id: req_01M5KN36P1JPANPMDW0HEWMM07 url_not_allowed: summary: The input URL breaks the URL policy value: error: type: invalid_request_error code: url_not_allowed message: image_url must use https param: image_url request_id: req_01M5KPQ1HMDVX7324R9FQFH87S idempotency_key_reused: summary: Same Idempotency-Key, different body value: error: type: invalid_request_error code: idempotency_key_reused message: >- this Idempotency-Key was already used with a different request body param: Idempotency-Key request_id: req_01M5KN36RZ8C1Q2T3V4W5X6Y7Z Unauthorized: description: >- The API key is missing, unknown, revoked or expired (`invalid_api_key`, `api_key_revoked`, `api_key_expired`). headers: X-Request-Id: $ref: '#/components/headers/X-Request-Id' content: application/json: schema: $ref: '#/components/schemas/Error' examples: invalid_api_key: summary: No key, or an unknown key value: error: type: authentication_error code: invalid_api_key message: >- missing API key: send Authorization: Bearer sk_live_… (or x-api-key) request_id: req_01M5KN14MXD6SJ01ZQ2FPS6Y8X api_key_revoked: summary: The key was revoked in the console value: error: type: authentication_error code: api_key_revoked message: this API key has been revoked request_id: req_01M5KN14PY5YH5QPA2QS7Y07Y4 PaymentRequired: description: >- Your spendable balance does not cover the estimated price (`insufficient_credits`). `details` carries `required` and `available`. headers: X-Request-Id: $ref: '#/components/headers/X-Request-Id' content: application/json: schema: $ref: '#/components/schemas/Error' example: error: type: billing_error code: insufficient_credits message: this task needs 60 credits, 25 are available request_id: req_01M5KPQ11B3NS7R5ZFFVZBD4W3 details: required: 60 available: 25 Forbidden: description: > The key lacks the scope (`insufficient_scope`), the caller's IP address is not on the key's allowlist (`ip_not_allowed`), or the account is suspended or not approved yet (`account_suspended`, `account_not_active`). headers: X-Request-Id: $ref: '#/components/headers/X-Request-Id' content: application/json: schema: $ref: '#/components/schemas/Error' examples: insufficient_scope: summary: The key lacks the scope value: error: type: permission_error code: insufficient_scope message: this key does not have the video:write scope request_id: req_01M5KN14S3T4U5V6W7X8Y9Z0A1 ip_not_allowed: summary: The caller is not on the key's IP allowlist value: error: type: permission_error code: ip_not_allowed message: requests from 203.0.113.9 are not allowed for this key request_id: req_01M5KN14T4U5V6W7X8Y9Z0A1B2 account_not_active: summary: The account is waiting for approval value: error: type: permission_error code: account_not_active message: this account is not active yet (pending approval) request_id: req_01M5KN14U5V6W7X8Y9Z0A1B2C3 Conflict: description: >- The task is already `completed` or `failed` (`task_already_terminal`), or a request with the same `Idempotency-Key` is still running (`idempotency_in_progress`). headers: X-Request-Id: $ref: '#/components/headers/X-Request-Id' content: application/json: schema: $ref: '#/components/schemas/Error' examples: task_already_terminal: summary: Cancel on a finished task value: error: type: conflict_error code: task_already_terminal message: task task_01J9X7Z0K7Q8W3F2P1N6M5V4R3 is already completed request_id: req_01M5KN37A1B2C3D4E5F6G7H8J9 idempotency_in_progress: summary: The first request with this key is still running value: error: type: conflict_error code: idempotency_in_progress message: a request with this Idempotency-Key is still being processed request_id: req_01M5KN37B2C3D4E5F6G7H8J9K0 TooManyRequests: description: > A limit of your plan was reached: the request rate (`rate_limit_exceeded`), the number of queued and processing tasks (`concurrency_limit_exceeded`) or the daily credit cap (`daily_cap_exceeded`). Wait `Retry-After` seconds before retrying. headers: Retry-After: $ref: '#/components/headers/Retry-After' X-RateLimit-Limit: $ref: '#/components/headers/X-RateLimit-Limit' X-RateLimit-Remaining: $ref: '#/components/headers/X-RateLimit-Remaining' X-RateLimit-Reset: $ref: '#/components/headers/X-RateLimit-Reset' X-Request-Id: $ref: '#/components/headers/X-Request-Id' content: application/json: schema: $ref: '#/components/schemas/Error' examples: rate_limit_exceeded: summary: Too many requests value: error: type: rate_limit_error code: rate_limit_exceeded message: rate limit exceeded for this account (10 rps, 300 rpm) request_id: req_01M5KN37C3D4E5F6G7H8J9K0L1 concurrency_limit_exceeded: summary: Too many tasks in flight value: error: type: rate_limit_error code: concurrency_limit_exceeded message: >- the account already has 20 tasks queued or processing (plan limit 20) request_id: req_01M5KN37D4E5F6G7H8J9K0L1M2 daily_cap_exceeded: summary: Daily credit cap reached value: error: type: rate_limit_error code: daily_cap_exceeded message: this account's daily credit cap (5000) would be exceeded request_id: req_01M5KN37E5F6G7H8J9K0L1M2N3 InternalError: description: >- An unexpected error (`internal_error`). Retry with backoff and the same `Idempotency-Key`. headers: X-Request-Id: $ref: '#/components/headers/X-Request-Id' content: application/json: schema: $ref: '#/components/schemas/Error' example: error: type: api_error code: internal_error message: an internal error occurred; retry with the same Idempotency-Key request_id: req_01M5KN37F6G7H8J9K0L1M2N3P4 ServiceUnavailable: description: >- Generation capacity is temporarily unavailable (`service_unavailable`). Nothing was charged; retry after `Retry-After` seconds with the same `Idempotency-Key`. headers: Retry-After: $ref: '#/components/headers/Retry-After' X-Request-Id: $ref: '#/components/headers/X-Request-Id' content: application/json: schema: $ref: '#/components/schemas/Error' example: error: type: api_error code: service_unavailable message: >- the pipeline cannot take new tasks right now, retry with the same Idempotency-Key request_id: req_01M5KPY92Y148QP01G532MM3BH securitySchemes: bearerAuth: type: http scheme: bearer description: > Your API key from the [developer console](https://fiveapi.ai), sent as `Authorization: Bearer sk_live_...`. The `x-api-key: sk_live_...` header is accepted as an alternative. ```` This documentation is built and hosted on [Mintlify](https://mintlify.com), a developer documentation platform.