## Update

**patch** `/assistants/{id}`

Update one or more fields on an existing assistant. Supports partial updates — only the fields you include in the request body will be changed. You can update the prompt, voice, first sentence, name, or any other assistant property without affecting the rest of the configuration.

### Path Parameters

- `id: string`

### Body Parameters

- `background_sound: optional "audio/office.ogg"`

  The background sound to play during the call. Useful to give the impression that your AI agent is in an office, in the street, or anywhere else you want.

  - `"audio/office.ogg"`

- `calendly: optional object { connection_id, event_type_id }`

  - `connection_id: string`

    The connection ID representing the link between your Calendly account and Revox.

  - `event_type_id: string`

    The event type ID representing the event type to schedule. (eg: https://api.calendly.com/event_types/b2330295-2a91-4a1d-bb73-99e7707663d5)

- `call_retry_config: optional object { calling_windows, max_retry_attempts, timezone }`

  Configuration for call retry behavior including time windows, delays, and max iterations. If not provided, defaults will be used.

  - `calling_windows: array of object { calling_window_end_time, calling_window_start_time, retry_delay_seconds }`

    - `calling_window_end_time: string`

      End time for the calling window in the recipient's timezone (or timezone_override if provided). Format: 'HH:mm' (24-hour) or 'H:mma' (12-hour). Examples: '17:00', '6pm'. Default: '18:00'.

    - `calling_window_start_time: string`

      Start time for the calling window in the recipient's timezone (or timezone_override if provided). Format: 'HH:mm' (24-hour) or 'H:mma' (12-hour). Examples: '09:00', '10am'. Default: '10:00'.

    - `retry_delay_seconds: number`

      Delay between retry attempts in seconds. Default: 7200 (2 hours).

  - `max_retry_attempts: number`

    Maximum number of call retry attempts. Default: 3.

  - `timezone: optional string`

    Optional IANA timezone identifier to override the automatic timezone detection from phone number. If not provided, timezone is determined from the recipient's phone number country code. Examples: 'America/New_York', 'Europe/Paris'.

- `end_of_call_sentence: optional string`

  Optional message to say when the agent decides to end the call.

- `faq_items: optional array of object { answer, question }`

  FAQ items to associate with this assistant. When provided, replaces all existing FAQ items.

  - `answer: string`

  - `question: string`

- `first_sentence: optional string`

  The first sentence to use for the call. This will be given to the LLM

- `first_sentence_delay_ms: optional number`

  Delay in milliseconds before speaking the first sentence. Default: 400.

- `first_sentence_mode: optional "generated" or "static" or "none"`

  How the first sentence should be handled. "generated" means the LLM will generate a response based on the first_sentence instruction. "static" means the first_sentence will be spoken exactly as provided. "none" means the agent will not speak first and will wait for the user.

  - `"generated"`

  - `"static"`

  - `"none"`

- `ivr_navigation_enabled: optional boolean`

  Enable IVR navigation tools. When enabled, the assistant can send DTMF tones and skip turns to navigate phone menus.

- `llm_model: optional object { name, type }  or object { openrouter_model_id, openrouter_provider, type }`

  - `UnionMember0 = object { name, type }`

    - `name: "gpt-4.1" or "ministral-3-8b-instruct"`

      - `"gpt-4.1"`

      - `"ministral-3-8b-instruct"`

    - `type: "dedicated-instance"`

      - `"dedicated-instance"`

  - `UnionMember1 = object { openrouter_model_id, openrouter_provider, type }`

    - `openrouter_model_id: string`

      The model ID to use from OpenRouter. eg: openai/gpt-4.1

    - `openrouter_provider: string`

      The provider to use from OpenRouter. eg: nebius, openai, azure, etc.

    - `type: "openrouter"`

      Use a model from OpenRouter.

      - `"openrouter"`

- `max_call_duration_secs: optional number`

  The maximum duration of the call in seconds. This is the maximum time the call will be allowed to run.

- `name: optional string`

- `prompt: optional string`

  The prompt to use for the call. This will be given to the LLM (gpt-4.1)

- `structured_output_config: optional array of object { name, required, type, 2 more }`

  The structured output config to use for the call. This is used to extract the data from the call (like email, name, company name, etc.).

  - `name: string`

  - `required: boolean`

  - `type: "string" or "number" or "boolean" or 3 more`

    - `"string"`

    - `"number"`

    - `"boolean"`

    - `"enum"`

    - `"date"`

    - `"datetime"`

  - `description: optional string`

  - `enum_options: optional array of string`

- `transfer_phone_number: optional string`

  Phone number to transfer calls to when users request to speak to a human agent in E.164 format (e.g. +1234567890).

- `voice: optional object { id, provider, speed }`

  The voice to use for the call. You can get the list of voices using the /voices endpoint

  - `id: string`

    The ID of the voice.

  - `provider: "cartesia" or "elevenlabs"`

    The provider of the voice.

    - `"cartesia"`

    - `"elevenlabs"`

  - `speed: optional number`

    The speed of the voice. Range depends on provider: Cartesia 0.6–1.5, ElevenLabs 0.7–1.2. Default is 1.0.

- `voicemail_message: optional string`

  If set, when voicemail is detected the agent will speak this message then hang up; if null, hang up immediately.

- `webhook_url: optional string`

  The webhook URL to call when the call is completed.

### Returns

- `assistant: object { id, background_sound, calendly, 20 more }`

  - `id: string`

  - `background_sound: "audio/office.ogg"`

    The background sound to play during the call. Useful to give the impression that your AI agent is in an office.

    - `"audio/office.ogg"`

  - `calendly: object { connection_id, event_type_id }`

    - `connection_id: string`

      The connection ID representing the link between your Calendly account and Revox.

    - `event_type_id: string`

      The event type ID representing the event type to schedule. (eg: https://api.calendly.com/event_types/b2330295-2a91-4a1d-bb73-99e7707663d5)

  - `call_retry_config: object { calling_windows, max_retry_attempts, timezone }`

    Configuration for call retry behavior including time windows, delays, and max iterations. If not provided, defaults will be used.

    - `calling_windows: array of object { calling_window_end_time, calling_window_start_time, retry_delay_seconds }`

      - `calling_window_end_time: string`

        End time for the calling window in the recipient's timezone (or timezone_override if provided). Format: 'HH:mm' (24-hour) or 'H:mma' (12-hour). Examples: '17:00', '6pm'. Default: '18:00'.

      - `calling_window_start_time: string`

        Start time for the calling window in the recipient's timezone (or timezone_override if provided). Format: 'HH:mm' (24-hour) or 'H:mma' (12-hour). Examples: '09:00', '10am'. Default: '10:00'.

      - `retry_delay_seconds: number`

        Delay between retry attempts in seconds. Default: 7200 (2 hours).

    - `max_retry_attempts: number`

      Maximum number of call retry attempts. Default: 3.

    - `timezone: optional string`

      Optional IANA timezone identifier to override the automatic timezone detection from phone number. If not provided, timezone is determined from the recipient's phone number country code. Examples: 'America/New_York', 'Europe/Paris'.

  - `created_at: unknown`

  - `end_of_call_sentence: string`

  - `first_sentence: string`

  - `first_sentence_delay_ms: number`

    Delay in milliseconds before speaking the first sentence. Default: 400.

  - `first_sentence_mode: "generated" or "static" or "none"`

    - `"generated"`

    - `"static"`

    - `"none"`

  - `ivr_navigation_enabled: boolean`

    Enable IVR navigation tools. When enabled, the assistant can send DTMF tones and skip turns to navigate phone menus.

  - `llm_model: object { name, type }  or object { openrouter_model_id, openrouter_provider, type }`

    - `UnionMember0 = object { name, type }`

      - `name: "gpt-4.1" or "ministral-3-8b-instruct"`

        - `"gpt-4.1"`

        - `"ministral-3-8b-instruct"`

      - `type: "dedicated-instance"`

        - `"dedicated-instance"`

    - `UnionMember1 = object { openrouter_model_id, openrouter_provider, type }`

      - `openrouter_model_id: string`

        The model ID to use from OpenRouter. eg: openai/gpt-4.1

      - `openrouter_provider: string`

        The provider to use from OpenRouter. eg: nebius, openai, azure, etc.

      - `type: "openrouter"`

        Use a model from OpenRouter.

        - `"openrouter"`

  - `max_call_duration_secs: number`

    The maximum duration of the call in seconds. This is the maximum time the call will be allowed to run.

  - `name: string`

  - `organization_id: string`

  - `prompt: string`

  - `structured_output_config: array of object { name, required, type, 2 more }`

    The structured output config to use for the call. This is used to extract the data from the call (like email, name, company name, etc.).

    - `name: string`

    - `required: boolean`

    - `type: "string" or "number" or "boolean" or 3 more`

      - `"string"`

      - `"number"`

      - `"boolean"`

      - `"enum"`

      - `"date"`

      - `"datetime"`

    - `description: optional string`

    - `enum_options: optional array of string`

  - `transfer_phone_number: string`

    Phone number to transfer calls to when users request to speak to a human agent.

  - `updated_at: unknown`

  - `voice: object { id, provider, speed }`

    - `id: string`

      The ID of the voice.

    - `provider: "cartesia" or "elevenlabs"`

      The provider of the voice.

      - `"cartesia"`

      - `"elevenlabs"`

    - `speed: optional number`

      The speed of the voice. Range depends on provider: Cartesia 0.6–1.5, ElevenLabs 0.7–1.2. Default is 1.0.

  - `voicemail_message: string`

    If set, when voicemail is detected the agent will speak this message then hang up; if null, hang up immediately.

  - `webhook_url: string`

    The webhook URL to call when the call is completed.

  - `faq_items: optional array of object { answer, question, id, 2 more }`

    - `answer: string`

    - `question: string`

    - `id: optional string`

    - `needs_human_answer: optional boolean`

    - `source: optional "human" or "ai"`

      - `"human"`

      - `"ai"`

  - `pending_faq_count: optional number`

### Example

```http
curl https://www.getrevox.com/api/assistants/$ID \
    -X PATCH \
    -H "Authorization: Bearer $REVOX_API_KEY"
```