Align speech words

curl --request POST 'https://api.voicecheap.ai/v1/actions/tts_align' \
  --header "x-api-key: $VOICECHEAP_API_KEY" \
  --header 'Content-Type: application/json' \
  --data '{"requestId":"284a861a-4da8-4d67-ad48-8123e76c8e91","historyId":"722c80c6412edd4c3dcd625061e1c1feafbb0d54274d95fd8b5ca047f8cdd23d"}'

const input = {
  requestId: '284a861a-4da8-4d67-ad48-8123e76c8e91',
  historyId: '722c80c6412edd4c3dcd625061e1c1feafbb0d54274d95fd8b5ca047f8cdd23d',
};
const response = await fetch('https://api.voicecheap.ai/v1/actions/tts_align', {
  method: 'POST',
  headers: {
    'x-api-key': process.env.VOICECHEAP_API_KEY,
    'Content-Type': 'application/json',
  },
  body: JSON.stringify(input),
});
const body = await response.json();
if (!response.ok) throw new Error(body.code + ': ' + body.message);
console.log(body);

import os
import requests

response = requests.post(
    "https://api.voicecheap.ai/v1/actions/tts_align",
    headers={"x-api-key": os.environ["VOICECHEAP_API_KEY"]},
    json={"requestId": "284a861a-4da8-4d67-ad48-8123e76c8e91", "historyId": "722c80c6412edd4c3dcd625061e1c1feafbb0d54274d95fd8b5ca047f8cdd23d"},
    timeout=120,
)
body = response.json()
if not response.ok:
    raise RuntimeError(f"{body.get('code')}: {body.get('message')}")
print(body)

{
  "data": {
    "requestId": "284a861a-4da8-4d67-ad48-8123e76c8e91",
    "status": "running",
    "pollAction": "action_request_get",
    "pollAfterSeconds": 5
  },
  "requestId": "284a861a-4da8-4d67-ad48-8123e76c8e91"
}

{
  "data": {
    "status": "ready",
    "wordAlignment": [
      {
        "text": "Hello",
        "startSeconds": 0,
        "endSeconds": 0.6,
        "sourceStartCharacterIndex": 0,
        "sourceEndCharacterIndex": 5
      },
      {
        "text": "world.",
        "startSeconds": 0.7,
        "endSeconds": 1.4,
        "sourceStartCharacterIndex": 6,
        "sourceEndCharacterIndex": 12
      }
    ]
  },
  "requestId": "284a861a-4da8-4d67-ad48-8123e76c8e91"
}

{
  "data": {
    "requestId": "284a861a-4da8-4d67-ad48-8123e76c8e91",
    "operation": "tts_align",
    "createdAt": 1792144800000,
    "updatedAt": 1792144820000,
    "status": "running",
    "pollAfterSeconds": 5
  },
  "requestId": "284a861a-4da8-4d67-ad48-8123e76c8e91"
}

{
  "data": {
    "requestId": "284a861a-4da8-4d67-ad48-8123e76c8e91",
    "operation": "tts_align",
    "createdAt": 1792144800000,
    "updatedAt": 1792144820000,
    "status": "completed",
    "resultStored": false,
    "message": "The action completed. Retrieve its output from the corresponding history or resource action."
  },
  "requestId": "284a861a-4da8-4d67-ad48-8123e76c8e91"
}

POST

actions

tts_align

curl --request POST 'https://api.voicecheap.ai/v1/actions/tts_align' \
  --header "x-api-key: $VOICECHEAP_API_KEY" \
  --header 'Content-Type: application/json' \
  --data '{"requestId":"284a861a-4da8-4d67-ad48-8123e76c8e91","historyId":"722c80c6412edd4c3dcd625061e1c1feafbb0d54274d95fd8b5ca047f8cdd23d"}'

const input = {
  requestId: '284a861a-4da8-4d67-ad48-8123e76c8e91',
  historyId: '722c80c6412edd4c3dcd625061e1c1feafbb0d54274d95fd8b5ca047f8cdd23d',
};
const response = await fetch('https://api.voicecheap.ai/v1/actions/tts_align', {
  method: 'POST',
  headers: {
    'x-api-key': process.env.VOICECHEAP_API_KEY,
    'Content-Type': 'application/json',
  },
  body: JSON.stringify(input),
});
const body = await response.json();
if (!response.ok) throw new Error(body.code + ': ' + body.message);
console.log(body);

import os
import requests

response = requests.post(
    "https://api.voicecheap.ai/v1/actions/tts_align",
    headers={"x-api-key": os.environ["VOICECHEAP_API_KEY"]},
    json={"requestId": "284a861a-4da8-4d67-ad48-8123e76c8e91", "historyId": "722c80c6412edd4c3dcd625061e1c1feafbb0d54274d95fd8b5ca047f8cdd23d"},
    timeout=120,
)
body = response.json()
if not response.ok:
    raise RuntimeError(f"{body.get('code')}: {body.get('message')}")
print(body)

{
  "data": {
    "requestId": "284a861a-4da8-4d67-ad48-8123e76c8e91",
    "status": "running",
    "pollAction": "action_request_get",
    "pollAfterSeconds": 5
  },
  "requestId": "284a861a-4da8-4d67-ad48-8123e76c8e91"
}

{
  "data": {
    "status": "ready",
    "wordAlignment": [
      {
        "text": "Hello",
        "startSeconds": 0,
        "endSeconds": 0.6,
        "sourceStartCharacterIndex": 0,
        "sourceEndCharacterIndex": 5
      },
      {
        "text": "world.",
        "startSeconds": 0.7,
        "endSeconds": 1.4,
        "sourceStartCharacterIndex": 6,
        "sourceEndCharacterIndex": 12
      }
    ]
  },
  "requestId": "284a861a-4da8-4d67-ad48-8123e76c8e91"
}

{
  "data": {
    "requestId": "284a861a-4da8-4d67-ad48-8123e76c8e91",
    "operation": "tts_align",
    "createdAt": 1792144800000,
    "updatedAt": 1792144820000,
    "status": "running",
    "pollAfterSeconds": 5
  },
  "requestId": "284a861a-4da8-4d67-ad48-8123e76c8e91"
}

{
  "data": {
    "requestId": "284a861a-4da8-4d67-ad48-8123e76c8e91",
    "operation": "tts_align",
    "createdAt": 1792144800000,
    "updatedAt": 1792144820000,
    "status": "completed",
    "resultStored": false,
    "message": "The action completed. Retrieve its output from the corresponding history or resource action."
  },
  "requestId": "284a861a-4da8-4d67-ad48-8123e76c8e91"
}

Prepare or retrieve word timestamps for an owned speech creation. Returns ready, processing, or unavailable. Completed alignment is cached.

POST https://api.voicecheap.ai/v1/actions/tts_align

Authentication and permissions

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: tts:write. An active paid subscription is required. Permissions do not change team roles, resource ownership, media credits, or plan limits.

Parameters

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}$.

string

required

History ID returned by tts_generate or tts_list.Pattern: ^(free-)?[0-9a-f]{64}$.

Complete input schema

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.

{
  "type": "object",
  "properties": {
    "requestId": {
      "description": "UUID v4 for this action. Reuse the same ID with identical arguments on retries.",
      "type": "string",
      "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}$"
    },
    "historyId": {
      "type": "string",
      "pattern": "^(free-)?[0-9a-f]{64}$",
      "description": "History ID returned by tts_generate or tts_list."
    }
  },
  "required": ["historyId"],
  "additionalProperties": false
}

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.

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.

curl --request POST 'https://api.voicecheap.ai/v1/actions/tts_align' \
  --header "x-api-key: $VOICECHEAP_API_KEY" \
  --header 'Content-Type: application/json' \
  --data '{"requestId":"284a861a-4da8-4d67-ad48-8123e76c8e91","historyId":"722c80c6412edd4c3dcd625061e1c1feafbb0d54274d95fd8b5ca047f8cdd23d"}'

const input = {
  requestId: '284a861a-4da8-4d67-ad48-8123e76c8e91',
  historyId: '722c80c6412edd4c3dcd625061e1c1feafbb0d54274d95fd8b5ca047f8cdd23d',
};
const response = await fetch('https://api.voicecheap.ai/v1/actions/tts_align', {
  method: 'POST',
  headers: {
    'x-api-key': process.env.VOICECHEAP_API_KEY,
    'Content-Type': 'application/json',
  },
  body: JSON.stringify(input),
});
const body = await response.json();
if (!response.ok) throw new Error(body.code + ': ' + body.message);
console.log(body);

import os
import requests

response = requests.post(
    "https://api.voicecheap.ai/v1/actions/tts_align",
    headers={"x-api-key": os.environ["VOICECHEAP_API_KEY"]},
    json={"requestId": "284a861a-4da8-4d67-ad48-8123e76c8e91", "historyId": "722c80c6412edd4c3dcd625061e1c1feafbb0d54274d95fd8b5ca047f8cdd23d"},
    timeout=120,
)
body = response.json()
if not response.ok:
    raise RuntimeError(f"{body.get('code')}: {body.get('message')}")
print(body)

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. Alignment status and word timestamps for the owned speech audio.

{
  "data": {
    "requestId": "284a861a-4da8-4d67-ad48-8123e76c8e91",
    "status": "running",
    "pollAction": "action_request_get",
    "pollAfterSeconds": 5
  },
  "requestId": "284a861a-4da8-4d67-ad48-8123e76c8e91"
}

{
  "data": {
    "status": "ready",
    "wordAlignment": [
      {
        "text": "Hello",
        "startSeconds": 0,
        "endSeconds": 0.6,
        "sourceStartCharacterIndex": 0,
        "sourceEndCharacterIndex": 5
      },
      {
        "text": "world.",
        "startSeconds": 0.7,
        "endSeconds": 1.4,
        "sourceStartCharacterIndex": 6,
        "sourceEndCharacterIndex": 12
      }
    ]
  },
  "requestId": "284a861a-4da8-4d67-ad48-8123e76c8e91"
}

{
  "data": {
    "requestId": "284a861a-4da8-4d67-ad48-8123e76c8e91",
    "operation": "tts_align",
    "createdAt": 1792144800000,
    "updatedAt": 1792144820000,
    "status": "running",
    "pollAfterSeconds": 5
  },
  "requestId": "284a861a-4da8-4d67-ad48-8123e76c8e91"
}

{
  "data": {
    "requestId": "284a861a-4da8-4d67-ad48-8123e76c8e91",
    "operation": "tts_align",
    "createdAt": 1792144800000,
    "updatedAt": 1792144820000,
    "status": "completed",
    "resultStored": false,
    "message": "The action completed. Retrieve its output from the corresponding history or resource action."
  },
  "requestId": "284a861a-4da8-4d67-ad48-8123e76c8e91"
}

Result fields

Field	Description
`data.status`	ready, processing, or unavailable.
`data.wordAlignment`	Word timestamps or null when no alignment is available.
`data.wordAlignment[].text`	Aligned word text.
`data.wordAlignment[].startSeconds`	Word start time in seconds.
`data.wordAlignment[].endSeconds`	Word end time in seconds.
`data.wordAlignment[].sourceStartCharacterIndex`	Start character index in spokenText, after delivery control tags have been removed.
`data.wordAlignment[].sourceEndCharacterIndex`	End character index in spokenText, after delivery control tags have been removed.

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.

curl --request POST 'https://api.voicecheap.ai/v1/actions/action_request_get' \
  --header "x-api-key: $VOICECHEAP_API_KEY" \
  --header 'Content-Type: application/json' \
  --data '{"requestId":"284a861a-4da8-4d67-ad48-8123e76c8e91","operation":"tts_align"}'

HTTP 200

{
  "data": {
    "requestId": "284a861a-4da8-4d67-ad48-8123e76c8e91",
    "operation": "tts_align",
    "status": "completed",
    "createdAt": 1792144800000,
    "updatedAt": 1792144820000,
    "resultStored": true,
    "result": {
      "status": "ready",
      "wordAlignment": [
        {
          "text": "Hello",
          "startSeconds": 0,
          "endSeconds": 0.6,
          "sourceStartCharacterIndex": 0,
          "sourceEndCharacterIndex": 5
        },
        {
          "text": "world.",
          "startSeconds": 0.7,
          "endSeconds": 1.4,
          "sourceStartCharacterIndex": 6,
          "sourceEndCharacterIndex": 12
        }
      ]
    }
  }
}

Operation notes

Use a UUID v4 requestId for this mutation and reuse it with identical arguments when retrying. Long-running actions first return a running request; this example is the completed handler result available from action_request_get.
status is ready with timestamps, processing while another alignment is active, or unavailable when alignment cannot currently be produced. processing and unavailable return wordAlignment: null.
Existing successful alignment is cached. For an app preview, only the audible portion of the script is aligned; completing the preview requires alignment of the new full audio.
Source character indices refer to spokenText with supported delivery control tags removed, as returned by tts_get.
A completed action request that returned processing keeps that recorded result on idempotent replay. Use tts_get to inspect available timestamps, or start a new alignment check with a new requestId after the active alignment finishes.
Speech history and custom voices belong to the authenticated account. Team billing does not grant access to another member’s speech or voices.

Usage

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

Errors

HTTP status	Code	Meaning or recovery
400	`CREDENTIAL_IN_QUERY`	Credentials were supplied in an access_token or api_key query parameter. Send credentials in headers.
400	`IDEMPOTENCY_CONFLICT`	The Idempotency-Key header and requestId body field must match.
400	`INVALID_REQUEST_ID`	Supply a UUID v4 requestId or Idempotency-Key.
400	`VALIDATION_ERROR`	The input does not match the action schema; inspect details for field errors.
401	`API_KEY_EXPIRED`	The API key has expired.
401	`INVALID_API_KEY`	Provide a valid, unexpired API key.
401	`INVALID_CREDENTIAL`	The Authorization header is malformed or conflicts with x-api-key.
401	`MISSING_CREDENTIAL`	No usable header credential was supplied, or it exceeded 4096 characters.
401	`USER_NOT_FOUND`	The credential’s account no longer exists.
403	`ACCOUNT_UNAVAILABLE`	The acting or billing account is unavailable or being deleted.
403	`AMBIGUOUS_TEAM_API_KEY`	The credential’s user belongs to more than one team, so the billing context is ambiguous.
403	`INSUFFICIENT_SCOPE`	Grant every required permission or choose another credential.
403	`INTEGRATION_PLAN_UNSUPPORTED`	The account’s integration limits could not be verified.
403	`SUBSCRIPTION_REQUIRED`	Use an active paid subscription.
403	`TEAM_OWNER_NOT_FOUND`	The effective team owner account could not be found.
404	`TEXT_TO_SPEECH_HISTORY_NOT_FOUND`	The speech history item does not exist or belongs to another account.
409	`CONCURRENT_ACTION_LIMIT_REACHED`	This account already has 10 integration actions running. Poll an existing request before starting another.
409	`IDEMPOTENCY_CONFLICT`	Reuse an identifier only with the same operation and arguments.
429	`INTEGRATION_MONTHLY_LIMIT_REACHED`	Wait for the monthly reset or change plan.
429	`INTEGRATION_RATE_LIMIT_REACHED`	Wait for Retry-After when present and use backoff.
500	`INTERNAL_ERROR`	Check saved request state and resource history before deciding to retry a mutation.
503	`ACTION_RESULT_UNAVAILABLE`	The action ran but its result could not be saved. Inspect saved request state and resource history before starting a new generation.
503	`SERVER_RESTARTING`	The server is restarting. Retry shortly and keep the same request identifier for a mutation.

{
  "code": "INSUFFICIENT_SCOPE",
  "message": "This credential does not permit the requested action.",
  "status": 403,
  "details": {
    "requiredScopes": ["tts:write"]
  }
}

Overview

Discovery

Account

Usage and activity

Settings and notifications

Team

Projects

Translation and dubbing

Transcripts and editing

Text to speech

Speech voices

Dubbing voices

Transcription

Subtitles and captions

Images

Thumbnails

Folders

Glossary

Webhooks

Publishing

Request status

OAuth and MCP protocol

Authentication and permissions

Parameters

Idempotency

Request examples

Response

Result fields

Recover and poll this request

Operation notes

Usage

Errors

​Authentication and permissions

​Parameters

​Idempotency

​Request examples

​Response

​Result fields

​Recover and poll this request

​Operation notes

​Usage

​Errors

Authentication and permissions

Parameters

Idempotency

Request examples

Response

Result fields

Recover and poll this request

Operation notes

Usage

Errors