Mux

Mux Transcription Vocabularies API

Transcription Vocabularies allows you to provide collections of phrases like proper nouns, technical jargon, and uncommon words as part of captioning workflows. When using Auto-Generated Captions, Transcription Vocabularies increase the likelihood of correct speech recognition for these words and phrases.

Documentation GitHub OpenAPI

Operations 5

Each operation below carries the questions people ask an LLM about it and the instructions they give an agent to run it. Generated by API Evangelist overlay

POST /video/v1/transcription-vocabularies Create a custom transcription vocabulary · Create a Transcription Vocabulary #

Ask an LLM

“How do I teach auto-captions brand names and jargon they keep getting wrong?”

“Can I give live captions a list of custom phrases to recognize?”

Tell an agent

Create a transcription vocabulary with phrases {phrases}.

Create a vocabulary named {name} containing {phrases}.

GET /video/v1/transcription-vocabularies List transcription vocabularies · List Transcription Vocabularies #

Ask an LLM

“Which custom transcription vocabularies have I created?”

“Can I page through my transcription vocabularies?”

Tell an agent

List my transcription vocabularies.

List transcription vocabularies, {limit} per page.

GET /video/v1/transcription-vocabularies/{TRANSCRIPTION_VOCABULARY_ID} Get a transcription vocabulary · Retrieve a Transcription Vocabulary #

Ask an LLM

“What phrases are in one of my transcription vocabularies?”

“Can I look up a transcription vocabulary by ID?”

Tell an agent

Show transcription vocabulary {transcription_vocabulary_id}.

List the phrases in vocabulary {transcription_vocabulary_id}.

DELETE /video/v1/transcription-vocabularies/{TRANSCRIPTION_VOCABULARY_ID} Delete a transcription vocabulary · Delete a Transcription Vocabulary #

Ask an LLM

“What happens to live streams using a vocabulary when I delete it?”

“How do I remove a transcription vocabulary?”

Tell an agent destructive · confirm first

Delete transcription vocabulary {transcription_vocabulary_id}.

Remove vocabulary {transcription_vocabulary_id} from my account.

PUT /video/v1/transcription-vocabularies/{TRANSCRIPTION_VOCABULARY_ID} Update a transcription vocabulary's phrases · Update a Transcription Vocabulary #

Ask an LLM

“Can I change a vocabulary while a live stream is using it?”

“How do I add new phrases to an existing transcription vocabulary?”

Tell an agent

Replace the phrases in vocabulary {transcription_vocabulary_id} with {phrases}.

Rename vocabulary {transcription_vocabulary_id} to {name} with phrases {phrases}.

Documentation

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Documentation

https://www.mux.com/docs/core/stream-video-files

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APIReference

https://www.mux.com/docs/api-reference

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Documentation

https://www.mux.com/docs/guides/start-live-streaming

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APIReference

https://www.mux.com/docs/api-reference#tag/Live-Streams

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Documentation

https://www.mux.com/docs/core/monitor-your-video-streaming-performance

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APIReference

https://www.mux.com/docs/api-reference#tag/Video-Views

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Documentation

https://www.mux.com/docs/guides/play-your-videos

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APIReference

https://www.mux.com/docs/api-reference#tag/Streaming

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Documentation

https://www.mux.com/docs/guides/get-images-from-a-video

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APIReference

https://www.mux.com/docs/api-reference#tag/Thumbnails

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Documentation

https://www.mux.com/docs/guides/mux-robots

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APIReference

https://www.mux.com/docs/api-reference#tag/Jobs

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Documentation

https://www.mux.com/docs/guides/signing-jwts

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APIReference

https://www.mux.com/docs/api-reference#tag/Signing-Keys

Specifications

⚙

OpenAPI

https://raw.githubusercontent.com/api-evangelist/mux-com/refs/heads/main/openapi/mux-com-transcription-vocabularies-api-openapi.yml

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OpenAPI Specification

openapi: 3.2.0
info:
  title: Mux Transcription Vocabularies API
  description: Mux is how developers build online video. This API encompasses both Mux Video and Mux Data functionality to help you build your video-related projects better and faster than ever before.
  version: v1
  contact:
    name: Mux DevEx
    url: https://docs.mux.com
    email: devex@mux.com
servers:
- url: https://api.mux.com
  description: Mux Production API
- url: https://image.mux.com
- url: https://stream.mux.com
- url: https://stats.mux.com
tags:
- name: Transcription Vocabularies
  description: Transcription Vocabularies allows you to provide collections of phrases like proper nouns, technical jargon, and uncommon words as part of captioning workflows. When using Auto-Generated Captions, Transcription Vocabularies increase the likelihood of correct speech recognition for these words and phrases.
  x-displayName: Transcription Vocabularies
paths:
  /video/v1/transcription-vocabularies:
    post:
      tags:
      - Transcription Vocabularies
      summary: Create a Transcription Vocabulary
      description: Create a new Transcription Vocabulary.
      operationId: create-transcription-vocabulary
      servers:
      - url: https://api.mux.com
      parameters: []
      requestBody:
        required: true
        content:
          application/json:
            schema:
              $ref: '#/components/schemas/CreateTranscriptionVocabularyRequest'
            example:
              name: Mux API Vocabulary
              phrases:
              - Mux
              - Live Stream
              - Playback ID
              - video encoding
      responses:
        '201':
          description: Transcription Vocabulary Created
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/TranscriptionVocabularyResponse'
              example:
                data:
                  id: VDm3npt2eaEDvz9emzun8Q
                  name: Mux API Vocabulary
                  phrases:
                  - Mux
                  - Live Stream
                  - Playback ID
                  - video encoding
                  created_at: '1609869152'
                  updated_at: '1609869152'
      security:
      - accessToken: []
      - authorizationToken: []
    get:
      tags:
      - Transcription Vocabularies
      summary: List Transcription Vocabularies
      description: List all Transcription Vocabularies.
      operationId: list-transcription-vocabularies
      servers:
      - url: https://api.mux.com
      parameters:
      - name: limit
        in: query
        description: Number of items to include in the response
        required: false
        schema:
          type: integer
          format: int32
          default: 10
          maximum: 10
      - $ref: '#/components/parameters/page'
      responses:
        '200':
          description: OK
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/ListTranscriptionVocabulariesResponse'
              example:
                data:
                - id: VDm3npt2eaEDvz9emzun8Q
                  name: Mux API Vocabulary
                  phrases:
                  - Mux
                  - Live Stream
                  - Playback ID
                  - video encoding
                  created_at: '1609869152'
                  updated_at: '1609870000'
                - id: M1lDlzSP102NgukTnyQyLqw
                  name: Video Codecs
                  phrases:
                  - h.264
                  - HEVC
                  - AV1
                  created_at: '1609869152'
                  updated_at: '1609870000'
      security:
      - accessToken: []
      - authorizationToken: []
  /video/v1/transcription-vocabularies/{TRANSCRIPTION_VOCABULARY_ID}:
    get:
      tags:
      - Transcription Vocabularies
      summary: Retrieve a Transcription Vocabulary
      description: Retrieves the details of a Transcription Vocabulary that has previously been created. Supply the unique Transcription Vocabulary ID and Mux will return the corresponding Transcription Vocabulary information. The same information is returned when creating a Transcription Vocabulary.
      operationId: get-transcription-vocabulary
      servers:
      - url: https://api.mux.com
      parameters:
      - $ref: '#/components/parameters/transcription_vocabulary_id'
      responses:
        '200':
          description: OK
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/TranscriptionVocabularyResponse'
              example:
                data:
                  id: VDm3npt2eaEDvz9emzun8Q
                  name: Mux API Vocabulary
                  phrases:
                  - Mux
                  - Live Stream
                  - Playback ID
                  - video encoding
                  created_at: '1609869152'
                  updated_at: '1609870000'
      security:
      - accessToken: []
      - authorizationToken: []
    delete:
      tags:
      - Transcription Vocabularies
      summary: Delete a Transcription Vocabulary
      description: Deletes a Transcription Vocabulary. The Transcription Vocabulary's ID will be disassociated from any live streams using it. Transcription Vocabularies can be deleted while associated live streams are active. However, the words and phrases in the deleted Transcription Vocabulary will remain attached to those streams while they are active.
      operationId: delete-transcription-vocabulary
      servers:
      - url: https://api.mux.com
      parameters:
      - $ref: '#/components/parameters/transcription_vocabulary_id'
      responses:
        '204':
          description: No Content
      security:
      - accessToken: []
      - authorizationToken: []
    put:
      tags:
      - Transcription Vocabularies
      summary: Update a Transcription Vocabulary
      description: Updates the details of a previously-created Transcription Vocabulary. Updates to Transcription Vocabularies are allowed while associated live streams are active. However, updates will not be applied to those streams while they are active.
      operationId: update-transcription-vocabulary
      servers:
      - url: https://api.mux.com
      parameters:
      - $ref: '#/components/parameters/transcription_vocabulary_id'
      requestBody:
        required: true
        content:
          application/json:
            schema:
              $ref: '#/components/schemas/UpdateTranscriptionVocabularyRequest'
            example:
              name: Mux API Vocabulary - Updated
              phrases:
              - Mux
              - Live Stream
              - RTMP
              - Stream Key
      responses:
        '200':
          description: OK
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/TranscriptionVocabularyResponse'
              example:
                data:
                  id: VDm3npt2eaEDvz9emzun8Q
                  name: Mux API Vocabulary - Updated
                  phrases:
                  - Mux
                  - Live Stream
                  - RTMP
                  - Stream Key
                  created_at: '1609869152'
                  updated_at: '1609870000'
      security:
      - accessToken: []
      - authorizationToken: []
components:
  schemas:
    UpdateTranscriptionVocabularyRequest:
      type: object
      properties:
        name:
          type: string
          description: The user-supplied name of the Transcription Vocabulary.
        phrases:
          type: array
          items:
            $ref: '#/components/schemas/TranscriptionVocabularyPhrase'
          maxItems: 1000
          description: Phrases, individual words, or proper names to include in the Transcription Vocabulary. When the Transcription Vocabulary is attached to a live stream's `generated_subtitles`, the probability of successful speech recognition for these words or phrases is boosted.
        passthrough:
          type: string
          description: Arbitrary user-supplied metadata set for the Transcription Vocabulary. Max 255 characters.
      required:
      - phrases
    CreateTranscriptionVocabularyRequest:
      type: object
      properties:
        name:
          type: string
          description: The user-supplied name of the Transcription Vocabulary.
        phrases:
          type: array
          items:
            $ref: '#/components/schemas/TranscriptionVocabularyPhrase'
          maxItems: 1000
          description: Phrases, individual words, or proper names to include in the Transcription Vocabulary. When the Transcription Vocabulary is attached to a live stream's `generated_subtitles`, the probability of successful speech recognition for these words or phrases is boosted.
        passthrough:
          type: string
          description: Arbitrary user-supplied metadata set for the Transcription Vocabulary. Max 255 characters.
      required:
      - phrases
    ListTranscriptionVocabulariesResponse:
      type: object
      properties:
        data:
          type: array
          items:
            $ref: '#/components/schemas/TranscriptionVocabulary'
    TranscriptionVocabulary:
      type: object
      required:
      - id
      - updated_at
      - created_at
      properties:
        id:
          type: string
          description: Unique identifier for the Transcription Vocabulary
        name:
          type: string
          description: The user-supplied name of the Transcription Vocabulary.
        phrases:
          type: array
          items:
            $ref: '#/components/schemas/TranscriptionVocabularyPhrase'
          maxItems: 1000
          description: Phrases, individual words, or proper names to include in the Transcription Vocabulary. When the Transcription Vocabulary is attached to a live stream's `generated_subtitles` configuration, the probability of successful speech recognition for these words or phrases is boosted.
        passthrough:
          type: string
          description: Arbitrary user-supplied metadata set for the Transcription Vocabulary. Max 255 characters.
        created_at:
          type: string
          format: int64
          description: Time the Transcription Vocabulary was created, defined as a Unix timestamp (seconds since epoch).
        updated_at:
          type: string
          format: int64
          description: Time the Transcription Vocabulary was updated, defined as a Unix timestamp (seconds since epoch).
    TranscriptionVocabularyPhrase:
      type: string
      description: A phrase or word belonging to a Transcription Vocabulary.
      minLength: 1
      maxLength: 32
    TranscriptionVocabularyResponse:
      type: object
      required:
      - data
      properties:
        data:
          $ref: '#/components/schemas/TranscriptionVocabulary'
  parameters:
    page:
      name: page
      in: query
      description: Offset by this many pages, of the size of `limit`
      required: false
      schema:
        type: integer
        format: int32
        default: 1
    transcription_vocabulary_id:
      name: TRANSCRIPTION_VOCABULARY_ID
      in: path
      description: The ID of the Transcription Vocabulary.
      required: true
      schema:
        type: string
  securitySchemes:
    accessToken:
      description: 'The Mux Video API uses an Access Token and Secret Key for authentication. If you haven''t already, [generate a new Access Token](https://dashboard.mux.com/settings/access-tokens) in the Access Token settings of your Mux account dashboard.


        Once you have an Access Token ID and Secret, you can then simply include those as the username (id) and password (secret) in the same way you use traditional basic auth.

        '
      scheme: basic
      type: http
    authorizationToken:
      description: 'OAuth authorization token, used as a Bearer Auth header

        '
      scheme: bearer
      type: http
x-tagGroups:
- name: Video
  tags:
  - Assets
  - Live Streams
  - Playback ID
  - URL Signing Keys
  - Direct Uploads
  - Delivery Usage
  - Playback Restrictions
  - DRM Configurations
  - Transcription Vocabularies
- name: Data
  tags:
  - Video Views
  - Errors
  - Filters
  - Exports
  - Metrics
  - Monitoring
  - Real-Time
  - Dimensions
  - Incidents
  - Annotations
  - View and Viewer Counts
- name: System
  tags:
  - Signing Keys
  - Utilities
- name: Robots
  tags:
  - Jobs
  - Ask Questions
  - Edit Captions
  - Find Key Moments
  - Generate Chapters
  - Moderate
  - Summarize
  - Translate Captions
- name: Playback
  tags:
  - Thumbnails
  - Animated Images
  - Storyboards
  - Streaming
  - Captions and Transcripts