# Update an assistant

`PATCH https://www.getrevox.com/api/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, required)

## Request body (JSON)

- `type` (enum (string), optional): Assistant kind. 'standalone' (default) is a normal assistant, 'multi-step' orchestrates a flow of sub-assistants, 'sub-assistant' is a step inside a multi-step flow (hidden from the assistants list). Flow transitions are managed via the /assistants/:id/edges endpoints, not on the assistant itself. One of: `standalone`, `multi-step`, `sub-assistant`.
- `position` (object, optional, nullable): Canvas position of this assistant's node in its multi-step flow editor.
  - `x` (number, required)
  - `y` (number, required)
- `start_step_name` (string, optional, nullable): Name of a multi-step flow's start step. Defaults to the assistant's name. Constraints: max length 255.
- `prompt` (string, optional): The prompt to use for the call. This will be given to the LLM (gpt-4.1)
- `post_call_prompt` (string, optional, nullable): Instructions the agent follows once the call has ended: who to email, when to text, what to post on Slack or Teams. Plain language, no template syntax. Empty or null means no post-call agent runs.
- `first_sentence` (string, optional): The first sentence to use for the call. This will be given to the LLM
- `first_sentence_mode` (enum (string), optional): 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. One of: `generated`, `static`, `none`.
- `end_of_call_sentence` (string, optional): Optional message to say when the agent decides to end the call.
- `voice` (object, optional): The voice to use for the call. You can get the list of voices using the /voices endpoint
  - `provider` (enum (string), required): The provider of the voice. One of: `cartesia`, `elevenlabs`, `gradium`.
  - `id` (string, required): The ID of the voice. Constraints: min length 1.
  - `speed` (number, optional): The speed of the voice. Range depends on provider: Cartesia 0.6–1.5, ElevenLabs 0.7–1.2, Gradium 0.6–1.5. Default is 1.0. Constraints: min 0.6, max 1.5.
  - `volume` (number, optional): Volume of the voice (Cartesia only). 0.5–2.0, default 1.0. Ignored for other providers. Constraints: min 0.5, max 2.
  - `model` (enum (string), optional): Cartesia TTS model (Cartesia only). Defaults to sonic-3.6 when omitted. Ignored for other providers. One of: `sonic-3`, `sonic-3.5`, `sonic-3.6`.
- `voice_languages` (array of object, optional, nullable): Extra languages for a multilingual assistant, each with its own voice (any provider). A call picks one with a `language` entry in its prompt_variables (a language code such as "es", or a name such as "Spanish"); otherwise the phone number's country picks one, and failing that the call runs in the language of `voice`, which cannot be listed here. A changed voice is applied to the calls in that language that have not completed yet; a language still used by such a call cannot be removed.
  - `language` (enum (string), required): The language contacts are called in with this voice. One of: `en`, `fr`, `es`, `de`, `it`, `pt`, `ru`, `zh`.
  - `voice` (object, required): The voice used for contacts whose language is this language.
    - `provider` (enum (string), required): The provider of the voice. One of: `cartesia`, `elevenlabs`, `gradium`.
    - `id` (string, required): The ID of the voice. Constraints: min length 1.
    - `speed` (number, optional): The speed of the voice. Range depends on provider: Cartesia 0.6–1.5, ElevenLabs 0.7–1.2, Gradium 0.6–1.5. Default is 1.0. Constraints: min 0.6, max 1.5.
    - `volume` (number, optional): Volume of the voice (Cartesia only). 0.5–2.0, default 1.0. Ignored for other providers. Constraints: min 0.5, max 2.
    - `model` (enum (string), optional): Cartesia TTS model (Cartesia only). Defaults to sonic-3.6 when omitted. Ignored for other providers. One of: `sonic-3`, `sonic-3.5`, `sonic-3.6`.
- `cartesia_dictionary_pronunciation_id` (string, optional, nullable): Optional Cartesia pronunciation dictionary ID to use for this assistant's calls. Set null to unlink it. Constraints: min length 1.
- `llm_model` (one of, optional)
  - One of, **Recommended** (object)
    - `type` (string (constant), required): The LLM Revox currently recommends for voice agents, chosen server-side and upgraded without any change on your side. No per-assistant configuration.
  - One of, **Gpt41Priority** (object)
    - `type` (string (constant), required): OpenAI gpt-4.1 on the priority tier, with gpt-4.1-mini answering a turn when gpt-4.1 is slow to respond. No per-assistant configuration.
  - One of, **Realtime** (object)
    - `type` (string (constant), required): Use a model from Realtime.
    - `provider` (enum (string), required): The provider to use from Realtime. eg: openai, google. One of: `openai`, `google`.
    - `realtime_model_id` (string, required): The model ID to use from Realtime. eg: gpt-4.1
    - `realtime_voice_id` (string, optional): Output voice for the realtime provider (e.g. OpenAI: marin; Gemini: Puck). Constraints: min length 1.
- `webhook_url` (string, optional): The webhook URL to call when the call is completed.
- `max_call_duration_secs` (number, optional): The maximum duration of the call in seconds. This is the maximum time the call will be allowed to run.
- `max_duration_end_message` (string, optional, nullable): Optional message the agent will say, without being interruptible, when the call reaches its max duration. Kept short so it fits inside the farewell buffer. If not set, the call ends silently. Constraints: max length 150.
- `structured_output_config` (array of [StructuredOutputField](https://www.getrevox.com/docs/api/objects/structured-output-field.md), optional): 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.).
- `structured_output_prompt` (string, optional, nullable): Custom prompt for structured data extraction. If not provided, a default prompt is used. Available variables: {{transcript}}, {{call_direction}}, {{user_phone_number}}, {{agent_phone_number}}.
- `call_retry_config` ([CallRetryConfig](https://www.getrevox.com/docs/api/objects/call-retry-config.md), optional)
- `background_sound` (enum (string), optional, nullable): Ambient background sound to play during the call. null/omitted disables it. One of: `audio/office.ogg`, `audio/waves.m4a`.
- `background_sound_volume` (number, optional): Volume of the ambient background sound (0 = silent, 1 = max). Constraints: min 0, max 1.
- `thinking_sound` (enum (string), optional, nullable): Audio clip to play while the agent is processing a response. One of the built-in LiveKit audio clips; null/omitted disables it. One of: `city-ambience.ogg`, `forest-ambience.ogg`, `office-ambience.ogg`, `crowded-room.ogg`, `keyboard-typing.ogg`, `keyboard-typing2.ogg`, `hold_music.ogg`.
- `thinking_sound_volume` (number, optional): Volume of the thinking sound (0 = silent, 1 = max). Constraints: min 0, max 1.
- `thinking_sound_probability` (number, optional): Probability [0..1] that the thinking sound plays on any given turn; otherwise the agent is silent while thinking. Constraints: min 0, max 1.
- `transfer_destinations` (array of object, optional, nullable): Where calls can be transferred to when users ask to speak to a human. With a single entry the assistant always transfers there; with several, it picks one at transfer time by applying the routing rules written in the assistant's own prompt (which refer to the destination labels). Empty or null disables transfer.
  - `label` (string, required): Human-meaningful name for this destination (e.g. "Sales"). The assistant's prompt refers to these labels when describing who to transfer to. Constraints: min length 1, max length 60.
  - `phone_number` (string, required): Destination phone number in E.164 format (e.g. +1234567890).
- `human_transfer_mode` (enum (string), optional, nullable): When transfer_destinations is non-empty: "warm" (AI bridges) or "cold" (SIP REFER; trunk must allow REFER/PSTN). Omit or null when transfer is disabled. One of: `warm`, `cold`.
- `warm_transfer_summary_instructions` (string, optional, nullable): When using warm transfer: extra instructions for the supervisor handoff summary. If null or empty, the API uses the product default briefing when the call is loaded for the agent.
- `warm_transfer_voice_speed` (number, optional, nullable): When using warm transfer: voice speed used only while the AI briefs the human colleague. Same range as voice.speed. Omit or null to brief at the assistant's voice speed. Constraints: min 0.6, max 1.5.
- `ivr_navigation_enabled` (boolean, optional): Enable IVR navigation tools. When enabled, the assistant can send DTMF tones and skip turns to navigate phone menus.
- `voicemail_message` (string, optional, nullable): If set, when voicemail is detected the agent will speak this message then hang up; if null, hang up immediately. Left on the first attempt only (second dial of a double call). Takes the same {{variables}} as the prompt (e.g. "Hi {{first_name}}, this is Julie from Acme, please call us back.").
- `stt_context` (object, optional, nullable): Assistant-level speech-to-text context: structured `general` key/value pairs plus a list of domain `terms`. Prompt-derived context is merged in without replacing existing entries.
  - `general` (array of object, required): Default: `[]`.
    - `key` (string, required): Constraints: min length 1.
    - `value` (string, required): Constraints: min length 1.
  - `terms` (array of string, required): Default: `[]`.
- `stt_model` (enum (string), optional): Transcriber (speech-to-text) model. Defaults to the newest Soniox realtime model when omitted. One of: `stt-rt-v4`, `stt-rt-v5`.
- `stt_endpoint_sensitivity` (number, optional, nullable): Soniox endpoint sensitivity override (-1 to 1). Higher values finalize transcripts sooner. Null or omitted: the agent's default tuning. Constraints: min -1, max 1.
- `stt_endpoint_latency_level` (integer, optional, nullable): Soniox endpoint latency adjustment level override (0 to 3). Higher values reduce endpoint latency at a slight accuracy cost. Null or omitted: the agent's default tuning. Constraints: min 0, max 3.
- `stt_bvc_filter_enabled` (boolean, optional): When false, the agent transcribes the raw caller track instead of the BVC noise-cancellation output. Default true.
- `krisp_viva_filter_enabled` (boolean, optional): When true, the agent's noise-cancellation filter is Krisp VIVA Tel instead of the legacy BVCTelephony. Default false.
- `first_sentence_delay_ms` (integer, optional): Delay in milliseconds before speaking the first sentence. Default: 400. Constraints: min 0, max 9007199254740991.
- `calendly` (object, optional, nullable): Deprecated: an assistant now books on any number of calendars, managed with the assistant calendars endpoints and listed in `calendars`. This field stands for the assistant's first ready calendar of this provider: setting it creates or updates that calendar, null removes it. The dashboard ignores it.
  - `connection_id` (string, required): The connection ID representing the link between your Calendly account and Revox.
  - `event_type_id` (string, required): The Calendly event type to schedule. (eg: https://api.calendly.com/event_types/b2330295-2a91-4a1d-bb73-99e7707663d5) Constraints: min length 1.
- `cal` (object, optional, nullable): Deprecated: an assistant now books on any number of calendars, managed with the assistant calendars endpoints and listed in `calendars`. This field stands for the assistant's first ready calendar of this provider: setting it creates or updates that calendar, null removes it. The dashboard ignores it.
  - `connection_id` (string, required): The connection ID representing the link between your Cal.com account and Revox.
  - `event_type_id` (string, required): The Cal.com event type to schedule. (eg: 7081322) Constraints: min length 1.
- `google_calendar` (object, optional, nullable): Deprecated: an assistant now books on any number of calendars, managed with the assistant calendars endpoints and listed in `calendars`. This field stands for the assistant's first ready calendar of this provider: setting it creates or updates that calendar, null removes it. The dashboard ignores it.
  - `calendar_id` (string, required): The Google calendar to book on. (eg: primary)
  - `time_zone` (string, required): The timezone of the opening hours. (eg: Europe/Paris)
  - `duration_minutes` (integer, required): Constraints: min 5, max 480. Default: `30`.
  - `days` (array of integer, required): The open days, 0 is Sunday. Default: `[1,2,3,4,5]`.
  - `start_time` (string, required): Constraints: pattern ^\d{2}:\d{2}$. Default: `"09:00"`.
  - `end_time` (string, required): Constraints: pattern ^\d{2}:\d{2}$. Default: `"18:00"`.
  - `google_meet` (boolean, required): Adds a Google Meet link to the meeting. Default: `true`.
  - `connection_id` (string, required): The connection ID representing the link between your Google account and Revox.
- `hubspot` (object, optional, nullable): HubSpot Meetings config. When set with at least one meeting link, the agent can read a rep's real availability and book the meeting natively in HubSpot during the call.
  - `connection_id` (string, required): The Nango connection ID linking the org's HubSpot account to Revox.
  - `precall_lookup_enabled` (boolean, required): Resolve the caller against HubSpot contacts before answering an inbound call, filling the contact_* prompt variables (contact_name, contact_owner, contact_lead_status, contact_has_open_deal). Off by default: it costs API calls before the phone is picked up. Default: `false`.
  - `meeting_links` (array of object, required): Scheduling pages the agent can book on during a call — typically one per sales rep plus a round-robin team page marked as the fallback. Default: `[]`.
    - `slug` (string, required): HubSpot scheduling page slug, as returned by the meeting-links API (e.g. 'julien-marchand'). Constraints: min length 1.
    - `label` (string, required): Name the agent recognises for this calendar (e.g. 'Julien Marchand'). Listed in the prompt and matched against what the caller asks for. Constraints: min length 1.
    - `duration_ms` (integer, required): Meeting duration in milliseconds, chosen among the durations the scheduling page offers (e.g. 1800000 for 30 minutes). Constraints: max 9007199254740991, > 0.
    - `is_fallback` (boolean, required): Marks the round-robin calendar the agent falls back to when the requested rep has no slot. At most one meeting link may set this.
    - `booking_url` (string, required, nullable): Public URL of the scheduling page (e.g. https://meetings-eu1.hubspot.com/julien). The agent books through the API and only texts this link to the caller when the booking fails and the call can receive an SMS. Null on calendars saved before this field existed. Default: `null`.
  - `post_call_sync` (object, optional): Sends call data back to HubSpot after the call. Off until set: connecting HubSpot to book meetings must not start writing to the CRM. Always present in responses; omit it on update to leave the current setting untouched.
    - `enabled` (boolean, required): Records calls in HubSpot after they end: the contact is created or updated from the phone number and the call is logged on its timeline. By default every call a person answered is recorded. When the post-call prompt talks about the CRM (in plain words or by mentioning the crm_push_call tool), the post-call agent decides instead which calls are recorded and what the logged call says. Default: `false`.
    - `field_mapping` (array of object, required): Maps extracted call fields (structured_output / prompt variables) onto HubSpot contact properties. Default: `[]`.
      - `source` (string, required): Source key to read from the call: a structured_output field name, falling back to a prompt variable of the same name. Constraints: min length 1.
      - `hubspot_property` (string, required): Destination HubSpot contact property, by internal name (e.g. 'email', 'company', or a custom 'budget'). Constraints: min length 1.
- `slack` (object, optional, nullable): Slack notification config. When set, posts a message to the chosen channel after a call ends with one of the configured outcomes.
  - `connection_id` (string, required): The Nango connection ID linking the org's Slack workspace to Revox.
  - `channels` (array of object, required): The Slack channels the post-call agent may post to. It resolves the channel it was told to use against this list and cannot reach any other.
    - `id` (string, required): The Slack channel ID (e.g. 'C01234567').
    - `name` (string, optional, nullable): Human-readable Slack channel name, cached for display in the UI and given to the LLM when the agent prompt routes by channel name.
- `teams` (object, optional, nullable): Microsoft Teams config. When set with at least one channel, the post-call agent can post to those channels when the post-call instructions ask for it.
  - `connection_id` (string, required): The Nango connection ID linking a Microsoft Teams account to Revox. Messages are posted as that account.
  - `channels` (array of object, required): The Teams channels the post-call agent may post to. It resolves the channel it was told to use against this list and cannot reach any other.
    - `id` (string, required): The Microsoft Teams channel ID (e.g. '19:561fbdbb...@thread.tacv2').
    - `name` (string, optional, nullable): Human-readable channel name, cached for display in the UI and given to the LLM when the agent prompt routes by channel name.
    - `team_id` (string, required): The ID of the team the channel belongs to. Needed to post.
    - `team_name` (string, optional, nullable): Human-readable team name. Channel names repeat across teams (every team has a 'General'), so the team name is what tells two of them apart.
- `zoho` (object, optional, nullable): Zoho CRM integration config. When set, upserts the prospect (keyed on phone) into the chosen module and attaches a Note with the call summary after a call ends with one of the configured outcomes.
  - `connection_id` (string, required): The Nango connection ID linking the org's Zoho CRM account to Revox.
  - `module` (string, required): Zoho module the prospect record is upserted into (e.g. 'Leads' or 'Contacts'). Constraints: min length 1.
  - `log_call_activity` (boolean, required): When true, also log the call as a record in Zoho's Calls module (related to the upserted prospect via Who_Id).
  - `field_mapping` (array of object, required): Maps extracted call fields (structured_output / prompt variables) onto Zoho field API names on the upserted record.
    - `source` (string, required): Source key to read from the call: a structured_output field name, falling back to a prompt variable of the same name. Constraints: min length 1.
    - `zoho_field` (string, required): Destination Zoho field API name on the upserted record (e.g. 'Email', 'Company', or a custom 'Budget__c'). Constraints: min length 1.
  - `template` (string, optional, nullable): Optional Note body template. Supports {{summary}}, {{outcome}}, {{phone}}, {{call_url}}, {{assistant_name}}, {{campaign_name}}, {{transcript}}, plus prompt_variables and structured_output keys. When null/empty a default note (outcome + summary + auto-listed extracted fields) is used.
- `custom_tools` (array of object, optional, nullable): Custom API tools the assistant can call during conversations. Each tool defines an HTTP endpoint with variable substitution.
  - `name` (string, required): Unique tool name in lowercase_snake_case (e.g. check_inventory) Constraints: min length 1, pattern ^[a-z][a-z0-9_]*$.
  - `description` (string, required): Human-readable description of what the tool does, used by the LLM to decide when to call it Constraints: min length 1.
  - `method` (enum (string), required): HTTP method to use when calling the API endpoint One of: `GET`, `POST`, `PUT`, `PATCH`, `DELETE`.
  - `url` (string, required): Full URL of the API endpoint. Supports {{variable}} placeholders for dynamic values Constraints: min length 1.
  - `headers` (array of object, required): HTTP headers to include in the request. Values support {{variable}} placeholders Default: `[]`.
    - `key` (string, required): Constraints: min length 1.
    - `value` (string, required)
  - `query_params` (array of object, required): Query string parameters appended to the URL. Values support {{variable}} placeholders Default: `[]`.
    - `key` (string, required): Constraints: min length 1.
    - `value` (string, required)
  - `body_template` (string, required, nullable): JSON body template for the request. Use quoted {{variable}} placeholders (e.g. "{{name}}") for dynamic values Default: `null`.
  - `input_schema` (array of [StructuredOutputField](https://www.getrevox.com/docs/api/objects/structured-output-field.md), required): Schema defining the parameters the LLM should extract from the conversation to pass to this tool
- `from_phone_number` (string, optional, nullable): Override the default outbound phone number for calls placed with this assistant. Must be a phone number owned by the organization in E.164 format (e.g. +1234567890). When null, the organization's default phone number is used.
- `logo_url` (string (uri), optional, nullable): Public URL of the brand logo shown on the assistant's demo page. Upload a new logo via POST /assistants/:id/logo. Set explicitly to null to clear it.
- `precall_lookup_url` (string, optional, nullable): Inbound calls only. URL fetched over HTTP GET right before the call is answered, with `{{phone}}` replaced by the caller's number in E.164 format (URL-encoded), to fill the `{{variable}}` placeholders the assistant declares. It answers either `{"prompt_variables": {...}}` or a flat JSON object whose top-level fields are the variables. The call is always answered: if the endpoint fails, takes more than 3 seconds, answers 404 or leaves a variable out, the missing variables are marked as not provided. Must be an http(s) URL containing `{{phone}}`. When null, no lookup is performed. Constraints: max length 2000.
- `precall_lookup_headers` (array of object, optional, nullable): HTTP headers sent with the pre-call lookup request, e.g. an API key. Null or empty when the endpoint needs none.
  - `key` (string, required): Constraints: max length 200, pattern ^[A-Za-z0-9!#$%&'*+.^_`|~-]+$.
  - `value` (string, required): Constraints: min length 1, max length 4000.
- `name` (string, optional)

## Example request

```bash
curl -X PATCH https://www.getrevox.com/api/assistants/3c90c3cc-0d44-4b50-8888-8dd25736052a \
  -H "Authorization: Bearer $REVOX_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "name": "Appointment reminder"
  }'
```

## Responses

### 200: Success

- `assistant` ([Assistant](https://www.getrevox.com/docs/api/objects/assistant.md), required)
- `unpatchedCallsNotice` (object, optional)
  - `count` (number, required)
  - `variables` (array of string, required)

### 400: Invalid request: the body or a parameter failed validation

- `message` (string, optional)
- `error` (string, optional)
- `bodyErrors` (object, optional): The validation errors returned from the API.
  - `issues` (array of object, required)
    - `path` (array of one of, required)
      - One of, **string** (string)
      - One of, **number** (number)
    - `message` (string, required)
    - `code` (string, optional)

### 404: Not found in your organization

- `error` (string, required)