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POST
Render subtitles into an uploaded video. Supply existing SRT or let VoiceCheap transcribe it. Saves the rendered video URL and its subtitle history. Returns a compact saved-result reference; use its getAction or downloadAction to retrieve the complete output.

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Authentication and permissions

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string
required
Send a VoiceCheap API key in this header. Authorization: Bearer with the same API key is also supported. OAuth access tokens are accepted only by MCP, not by this REST endpoint.
Required permissions: subtitles:write. An active paid subscription is required. Permissions do not change team roles, resource ownership, media credits, or plan limits.

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Parameters

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string
required
An owned fileKey returned by a completed upload or media import. Each generation consumes its uploaded source.Minimum length: 1. Maximum length: 1024.
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string
Text value.Minimum length: 1. Maximum length: 255. Pattern: ^[^/\\\r\n\0]+$.
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array
List of values. See the complete input schema for its item structure.Maximum items: 100.
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string
Optional at the transport boundary: the server injects an identifier before validation when omitted. Supply your own stable UUID v4 to recover safely from a lost response.Format: “uuid”. Pattern: ^[0-9a-fA-F]{8}-[0-9a-fA-F]{4}-4[0-9a-fA-F]{3}-[89abAB][0-9a-fA-F]{3}-[0-9a-fA-F]{12}$.
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object
JSON object. See the complete input schema for its nested fields.
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string
Text value.Minimum length: 1. Maximum length: 2097152.
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string
Text value.Minimum length: 2. Maximum length: 60.
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object
JSON object. See the complete input schema for its nested fields.
The JSON Schema below preserves the exact field names, nested types, defaults, bounds, and accepted values exposed by discovery. Additional cross-field rules are listed in the operation notes.

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Idempotency

Use a UUID v4 in requestId or the Idempotency-Key HTTP header for each mutation. Reuse the same identifier and identical arguments after a network failure. If both are supplied, they must match. Replaying a saved request does not repeat the operation or charge another monthly call. Failed or interrupted requests are not restarted automatically. Every mutation can return HTTP 202 when a retry finds the same request still running, even when its first execution is normally synchronous. If execution completed but resultStored is false, a retry returns HTTP 200 with saved request state instead of the original result. Retrieve the output through its domain history, result, or download action.

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Request examples

Replace example resource identifiers and media keys with values returned for your account. Keep the request identifier stable when retrying the same mutation.

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Response

This operation returns HTTP 202 while running. Save requestId and poll action_request_get with that identifier and the original operation name. Polling states are running, completed, failed, and interrupted. A completed result can point to a separate media job; continue with the operation-specific status or output action. A saved rendered-subtitle result reference. Its complete JSON contains srt, sourceSrt, subtitledVideoUrl and optional detectedLanguage.

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Result fields

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Recover and poll this request

Use the same identifier even after a lost connection. If resultStored is false, retrieve the output through the corresponding history, result, or download action. Never start a second generation merely to check progress.
HTTP 200

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Operation notes

  • Requires a paid subscription and the action permission. The actor’s personal tool plan is rechecked at execution; saved tools and upload references belong to that actor, including when the credential is associated with a team.
  • A successful action uses one shared monthly API/MCP call. Beginner allows 500, Starter 5,000 and Creator 25,000 calls/month; Pro, Scale and Enterprise have no monthly ceiling. Per-minute limits still apply: 30, 60, 120, 180, 300 and 600 respectively. Tool generation allowances are separate.
  • Use a UUID v4 requestId, or an identical Idempotency-Key header, and retain the same action, ID and arguments on retries. A cached replay does not use another monthly call.
  • This is an asynchronous action. The initial transport result is a running request with pollAction; poll action_request_get with this operation and the original requestId. The completed operation result shown here is a compact saved-output reference, not the generated body.
  • Complete output is saved under authenticated ownership in encrypted storage independently of the bounded action polling cache. Call the returned getAction with resultId and includeContent: true for structured JSON, or downloadAction with resultId for JSON text. listAction provides a recovery route when only the original request is known.
  • The saved JSON is limited to 32 MiB. Metadata never exposes its storage encryption key or an unauthenticated transcript download URL.
  • Successful generation settles one personal tool allowance. Failed generation normally releases its tool reservation. When output persistence is uncertain, inspect the same request and saved-result history before generating again; the server retains the reservation to prevent duplicate usage.
  • Higher plans without a monthly integration ceiling still have the tool-specific daily allowances and media limits below. These standalone actions use their tool allowance rather than dubbing minutes or TTS characters.
  • Use fileKey from a completed owned upload or import and treat it as single-use. Once media processing begins, cleanup deletes the source after success or processing failure. Validation or allowance rejection before processing can leave it intact. Reuse the original requestId to recover the accepted generation before starting another.
  • The source must contain video, be at most 300 MiB and no longer than 2 hours. Supply existing SRT in srtContent, or omit it to generate subtitles from an audio stream. Without supplied SRT, the source must also contain audio.
  • subtitleStyle is a complete object: fontFamily sans/serif/mono, fontSize small/medium/large, textColor white/yellow/cyan, backgroundStyle outline/box/shadow and position bottom/middle. subtitleLayout requires both supported layout fields.
  • Daily allowance per tool: Beginner 5, Starter 15, Creator 30, Pro 60, Scale 100 and Enterprise 100 successful generations. It is shared with the corresponding web tool and uses the account tool reset window.
  • subtitles_burn and subtitles_burn_youtube share the add-subtitles tool allowance. Rendering with supplied subtitles still uses one generation. Rendering creates a separate output video and a best-effort subtitle-burn history entry.
  • The operation returns only the four subtitle/output fields in its saved JSON. To refresh the video read URL, use subtitles_burn_history_list/get and subtitles_burn_download.

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Usage

Each successful invocation consumes one monthly API/MCP call. Media credits and the operation’s own generation allowances also apply.

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Errors