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Place a call

call.create(**kwargs) -> CallCreateResponse { call }
POST/call

Place a new outbound call order. Provide either an existing assistant ID or a custom assistant configuration. The call can be scheduled for a specific time or started immediately. A single call order may be resolved over multiple call attempts spanning up to a few days, with automatic retries when voicemail is detected. You can also set concurrency limits and pass prompt variables for dynamic personalization.

ParametersExpand Collapse
phone_number: String

The phone number to call in the E.164 format. Example: +1234567890

assistant: { prompt, after_call_sms_prompt, background_sound, 30 more}

You can provide a custom assistant configuration here. If you don't provide an assistant_id, this assistant object will be used for this call.

prompt: String

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

after_call_sms_prompt: String

Prompt / instructions for the after-call SMS. Supports {{variable}} placeholders. When null, no after-call SMS is sent.

background_sound: :"audio/office.ogg"

Ambient background sound to play during the call. null/omitted disables it.

background_sound_volume: Float

Volume of the ambient background sound (0 = silent, 1 = max).

minimum0
maximum1
calendly: { 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: { allowed_days, call_twice_in_a_row, calling_windows, 2 more}

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

allowed_days: Array[:monday | :tuesday | :wednesday | 4 more]

Days of the week when calls are allowed, in the recipient's timezone. Default: Monday through Friday.

One of the following:
:monday
:tuesday
:wednesday
:thursday
:friday
:saturday
:sunday
call_twice_in_a_row: bool

If true and max_retry_attempts >= 2, attempt #2 fires immediately (skipping retry_delay_seconds) when attempt #1 didn't reach a human. Calling-window/allowed-days checks still apply. Only affects the 1→2 transition. Default: false.

calling_windows: Array[{ 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: Integer

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

exclusiveMinimum0
maximum9007199254740991
max_retry_attempts: Integer

Maximum number of call retry attempts. Default: 3.

exclusiveMinimum0
maximum9007199254740991
timezone: 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'.

custom_tools: Array[{ body_template, description, headers, 5 more}]

Custom API tools the assistant can call during conversations. Each tool defines an HTTP endpoint with variable substitution.

body_template: String

JSON body template for the request. Use quoted {{variable}} placeholders (e.g. "{{name}}") for dynamic values

description: String

Human-readable description of what the tool does, used by the LLM to decide when to call it

minLength1
headers: Array[{ key, value}]

HTTP headers to include in the request. Values support {{variable}} placeholders

key: String
minLength1
value: String
input_schema: Array[{ name, required, type, 2 more}]

Schema defining the parameters the LLM should extract from the conversation to pass to this tool

name: String
minLength1
required: bool
type: :string | :number | :boolean | 3 more
One of the following:
:string
:number
:boolean
:enum
:date
:datetime
description: String
enum_options: Array[String]
method_: :GET | :POST | :PUT | 2 more

HTTP method to use when calling the API endpoint

One of the following:
:GET
:POST
:PUT
:PATCH
:DELETE
name: String

Unique tool name in lowercase_snake_case (e.g. check_inventory)

minLength1
query_params: Array[{ key, value}]

Query string parameters appended to the URL. Values support {{variable}} placeholders

key: String
minLength1
value: String
url: String

Full URL of the API endpoint. Supports {{variable}} placeholders for dynamic values

minLength1
email_notification_address: String

Email address to receive notifications when a call ends with a matching outcome.

formatemail
email_notification_outcomes: Array[:not_interested | :interested | :completed | 3 more]

Which call outcomes trigger an email notification. E.g. ["interested", "completed"].

One of the following:
:not_interested
:interested
:completed
:requested_callback_later
:requested_callback_new_number
:do_not_contact
end_of_call_sentence: String

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

faq_items: Array[{ answer, question}]

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

answer: String
question: String
first_sentence: String

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

first_sentence_delay_ms: Integer

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

minimum0
maximum9007199254740991
first_sentence_mode: :generated | :static | :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.

One of the following:
:generated
:static
:none
from_phone_number: String

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.

human_transfer_mode: :warm | :cold

When transfer_phone_number is set: "warm" (AI bridges) or "cold" (SIP REFER; trunk must allow REFER/PSTN). Omit or null when transfer is disabled.

One of the following:
:warm
:cold
ivr_navigation_enabled: bool

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

llm_model: { name, type} | { openrouter_model_id, openrouter_provider, type} | { api_key, api_url, model_name, type} | { provider, realtime_model_id, type, realtime_voice_id}
One of the following:
class UnionMember0 { name, type }
name: :"gpt-4.1" | :"ministral-3-8b-instruct"
One of the following:
:"gpt-4.1"
:"ministral-3-8b-instruct"
type: :"dedicated-instance"
class UnionMember1 { 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.

class UnionMember2 { api_key, api_url, model_name, type }
api_key: String

API key sent as Bearer token to the custom endpoint.

minLength1
api_url: String

Base URL for the OpenAI-compatible API, e.g. https://api.together.xyz/v1

formaturi
model_name: String

Model name as expected by the provider, e.g. meta-llama/llama-3-70b

minLength1
type: :custom

OpenAI-compatible chat completions API (bring your own endpoint and key).

class UnionMember3 { provider, realtime_model_id, type, realtime_voice_id }
provider: :openai | :google

The provider to use from Realtime. eg: openai, google.

One of the following:
:openai
:google
realtime_model_id: String

The model ID to use from Realtime. eg: gpt-4.1

type: :realtime

Use a model from Realtime.

realtime_voice_id: String

Output voice for the realtime provider (e.g. OpenAI: marin; Gemini: Puck).

minLength1
max_call_duration_secs: Float

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 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.

maxLength150
sms_enabled: bool

Enable SMS tool during calls. When enabled, the agent can send SMS messages to the user on the call.

sms_template: String

Hardcoded SMS template to send during calls. When set, this exact text is sent instead of letting the agent generate the message. Supports {{variable}} placeholders.

structured_output_config: Array[{ 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
minLength1
required: bool
type: :string | :number | :boolean | 3 more
One of the following:
:string
:number
:boolean
:enum
:date
:datetime
description: String
enum_options: Array[String]
structured_output_prompt: String

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}}.

thinking_sound: :"city-ambience.ogg" | :"forest-ambience.ogg" | :"office-ambience.ogg" | 4 more

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 the following:
:"city-ambience.ogg"
:"forest-ambience.ogg"
:"office-ambience.ogg"
:"crowded-room.ogg"
:"keyboard-typing.ogg"
:"keyboard-typing2.ogg"
:"hold_music.ogg"
thinking_sound_probability: Float

Probability [0..1] that the thinking sound plays on any given turn; otherwise the agent is silent while thinking.

minimum0
maximum1
thinking_sound_volume: Float

Volume of the thinking sound (0 = silent, 1 = max).

minimum0
maximum1
transfer_phone_number: String

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

voice: { id, provider, speed, volume}

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.

minLength1
provider: :cartesia | :elevenlabs

The provider of the voice.

One of the following:
:cartesia
:elevenlabs
speed: Float

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

minimum0.6
maximum1.5
volume: Float

Volume of the voice (Cartesia only). 0.5–2.0, default 1.0. Ignored for other providers.

minimum0.5
maximum2
voicemail_message: String

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

voicemail_sms_prompt: String

SMS message to send when the call reaches voicemail. Supports {{variable}} placeholders. When null, no SMS is sent on voicemail.

warm_transfer_summary_instructions: String

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.

webhook_url: String

The webhook URL to call when the call is completed.

assistant_id: String

The ID of the assistant to use for this call.

formatuuid
concurrency: { key, max}

Limit the number of concurrent calls for a given concurrency key.

key: String

The key for which you want to limit the number of concurrent calls.

max: Float

The maximum number of concurrent calls to allow for the given concurrency key.

minimum1
force_now: bool

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

from_phone_number: String

The phone number to use for making the call (e.g., +1234567890). If not provided, uses the default trunk.

metadata: Hash[Symbol, String]

Metadata to store with the call.

prompt_variables: Hash[Symbol, String]

Variables to interpolate into the prompt. Wether you use an assistant_id or an assistant object, this will be used to interpolate the variables into the prompt.

scheduled_at: Time | untyped

Schedule the call to start at a specific date and time (ISO 8601 format). If not provided, the call will start immediately.

One of the following:
Time
untyped
ReturnsExpand Collapse
class CallCreateResponse { call }
call: { id, assistant, call_attempts, 20 more}

This represent a call "order" that was requested by the user. A call order can be resolved over multiple call attempts spanning up to a few days.

id: String

The ID of the call.

assistant: { id, after_call_sms_prompt, background_sound, 36 more}
id: String
after_call_sms_prompt: String

Prompt / instructions for the after-call SMS. Supports {{variable}} placeholders. When null, no after-call SMS is sent.

background_sound: :"audio/office.ogg"

Ambient background sound to play during the call. null disables it.

background_sound_volume: Float

Volume of the ambient background sound (0 = silent, 1 = max).

minimum0
maximum1
calendly: { 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: { allowed_days, call_twice_in_a_row, calling_windows, 2 more}

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

allowed_days: Array[:monday | :tuesday | :wednesday | 4 more]

Days of the week when calls are allowed, in the recipient's timezone. Default: Monday through Friday.

One of the following:
:monday
:tuesday
:wednesday
:thursday
:friday
:saturday
:sunday
call_twice_in_a_row: bool

If true and max_retry_attempts >= 2, attempt #2 fires immediately (skipping retry_delay_seconds) when attempt #1 didn't reach a human. Calling-window/allowed-days checks still apply. Only affects the 1→2 transition. Default: false.

calling_windows: Array[{ 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: Integer

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

exclusiveMinimum0
maximum9007199254740991
max_retry_attempts: Integer

Maximum number of call retry attempts. Default: 3.

exclusiveMinimum0
maximum9007199254740991
timezone: 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: untyped
custom_tools: Array[{ body_template, description, headers, 5 more}]
body_template: String

JSON body template for the request. Use quoted {{variable}} placeholders (e.g. "{{name}}") for dynamic values

description: String

Human-readable description of what the tool does, used by the LLM to decide when to call it

minLength1
headers: Array[{ key, value}]

HTTP headers to include in the request. Values support {{variable}} placeholders

key: String
minLength1
value: String
input_schema: Array[{ name, required, type, 2 more}]

Schema defining the parameters the LLM should extract from the conversation to pass to this tool

name: String
minLength1
required: bool
type: :string | :number | :boolean | 3 more
One of the following:
:string
:number
:boolean
:enum
:date
:datetime
description: String
enum_options: Array[String]
method_: :GET | :POST | :PUT | 2 more

HTTP method to use when calling the API endpoint

One of the following:
:GET
:POST
:PUT
:PATCH
:DELETE
name: String

Unique tool name in lowercase_snake_case (e.g. check_inventory)

minLength1
query_params: Array[{ key, value}]

Query string parameters appended to the URL. Values support {{variable}} placeholders

key: String
minLength1
value: String
url: String

Full URL of the API endpoint. Supports {{variable}} placeholders for dynamic values

minLength1
email_notification_address: String

Email address to receive notifications when a call ends with a matching outcome.

formatemail
email_notification_outcomes: Array[:not_interested | :interested | :completed | 3 more]

Which call outcomes trigger an email notification. E.g. ["interested", "completed"].

One of the following:
:not_interested
:interested
:completed
:requested_callback_later
:requested_callback_new_number
:do_not_contact
end_of_call_sentence: String
first_sentence: String
first_sentence_delay_ms: Integer

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

minimum-9007199254740991
maximum9007199254740991
first_sentence_mode: :generated | :static | :none
One of the following:
:generated
:static
:none
from_phone_number: String

Override the default outbound phone number for calls placed with this assistant. When null, the organization's default phone number is used.

human_transfer_mode: :warm | :cold

Warm or cold transfer when transfer_phone_number is set; null when transfer is not configured.

One of the following:
:warm
:cold
ivr_navigation_enabled: bool

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

llm_model: { name, type} | { openrouter_model_id, openrouter_provider, type} | { api_key, api_url, model_name, type} | { provider, realtime_model_id, type, realtime_voice_id}
One of the following:
class UnionMember0 { name, type }
name: :"gpt-4.1" | :"ministral-3-8b-instruct"
One of the following:
:"gpt-4.1"
:"ministral-3-8b-instruct"
type: :"dedicated-instance"
class UnionMember1 { 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.

class UnionMember2 { api_key, api_url, model_name, type }
api_key: String

API key sent as Bearer token to the custom endpoint.

minLength1
api_url: String

Base URL for the OpenAI-compatible API, e.g. https://api.together.xyz/v1

formaturi
model_name: String

Model name as expected by the provider, e.g. meta-llama/llama-3-70b

minLength1
type: :custom

OpenAI-compatible chat completions API (bring your own endpoint and key).

class UnionMember3 { provider, realtime_model_id, type, realtime_voice_id }
provider: :openai | :google

The provider to use from Realtime. eg: openai, google.

One of the following:
:openai
:google
realtime_model_id: String

The model ID to use from Realtime. eg: gpt-4.1

type: :realtime

Use a model from Realtime.

realtime_voice_id: String

Output voice for the realtime provider (e.g. OpenAI: marin; Gemini: Puck).

minLength1
max_call_duration_secs: Float

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 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 null, the call ends silently.

maxLength150
name: String
organization_id: String
prompt: String
sms_enabled: bool

Enable SMS tool during calls. When enabled, the agent can send SMS messages to the user on the call.

sms_template: String

Hardcoded SMS template to send during calls. When set, this exact text is sent instead of letting the agent generate the message. Supports {{variable}} placeholders.

structured_output_config: Array[{ 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
minLength1
required: bool
type: :string | :number | :boolean | 3 more
One of the following:
:string
:number
:boolean
:enum
:date
:datetime
description: String
enum_options: Array[String]
structured_output_prompt: String

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}}.

thinking_sound: :"city-ambience.ogg" | :"forest-ambience.ogg" | :"office-ambience.ogg" | 4 more

Audio clip to play while the agent is processing a response. One of the built-in LiveKit audio clips; null disables it.

One of the following:
:"city-ambience.ogg"
:"forest-ambience.ogg"
:"office-ambience.ogg"
:"crowded-room.ogg"
:"keyboard-typing.ogg"
:"keyboard-typing2.ogg"
:"hold_music.ogg"
thinking_sound_probability: Float

Probability [0..1] that the thinking sound plays on any given turn; otherwise the agent is silent while thinking.

minimum0
maximum1
thinking_sound_volume: Float

Volume of the thinking sound (0 = silent, 1 = max).

minimum0
maximum1
transfer_phone_number: String

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

updated_at: untyped
voice: { id, provider, speed, volume}
id: String

The ID of the voice.

minLength1
provider: :cartesia | :elevenlabs

The provider of the voice.

One of the following:
:cartesia
:elevenlabs
speed: Float

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

minimum0.6
maximum1.5
volume: Float

Volume of the voice (Cartesia only). 0.5–2.0, default 1.0. Ignored for other providers.

minimum0.5
maximum2
voicemail_message: String

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

voicemail_sms_prompt: String

Prompt / instructions for the voicemail SMS. Supports {{variable}} placeholders. When null, no SMS is sent on voicemail.

warm_transfer_summary_instructions: String

Warm transfer only: instructions for the supervisor handoff summary; null when not configured or cold transfer.

webhook_url: String

The webhook URL to call when the call is completed.

faq_items: Array[{ answer, question, id, 2 more}]
answer: String
question: String
id: String
needs_human_answer: bool
source: :human | :ai
One of the following:
:human
:ai
pending_faq_count: Float
call_attempts: Array[{ id, answered_at, dial_error, 10 more}]

All call attempts for this call order, ordered by most recent first.

id: String

The ID of the call attempt.

answered_at: untyped

The time the call was answered.

dial_error: :number_non_attributed | :too_many_calls | :busy | 5 more

The SIP error that occurred.

One of the following:
:number_non_attributed
:too_many_calls
:busy
:temporarily_unavailable
:no_answer
:no_international_permission
:precondition_failed
:non_classified_error
ended_at: untyped

The time the call ended.

phone_number: String

The phone number that was called. Formatted in E.164 format. Example: +1234567890

recording_url: String

The URL of the audio recording of the call.

result: :IVR | :voicemail | :human | 2 more
One of the following:
:IVR
:voicemail
:human
:unknown
:"ios-screening-filter"
started_at: untyped

The time the call started.

status: :queued | :ringing | :ongoing | 2 more

The status of the call attempt.

One of the following:
:queued
:ringing
:ongoing
:completed
:error
end_reason: String

Reason for ending the call when ended_by is 'agent'. E.g. 'tool_end_call', 'voicemail', 'transfer', 'ivr_no_navigate'.

ended_by: :agent | :user | :system

Who ended the call: 'agent' (AI agent), 'user' (caller/callee hung up), or 'system' (e.g. max duration limit).

One of the following:
:agent
:user
:system
structured_output: Hash[Symbol, untyped]

The data extracted from the call, using the structured output config from the parent call object.

transcript: Array[{ content, role, tool_arguments, 3 more}]

The transcript of the call.

content: String
role: :user | :assistant | :tool
One of the following:
:user
:assistant
:tool
tool_arguments: Hash[Symbol, untyped] | String
One of the following:
Hash[Symbol, untyped]
String
tool_is_error: bool
tool_name: String
tool_output: String
call_retry_config: { allowed_days, call_twice_in_a_row, calling_windows, 2 more}

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

allowed_days: Array[:monday | :tuesday | :wednesday | 4 more]

Days of the week when calls are allowed, in the recipient's timezone. Default: Monday through Friday.

One of the following:
:monday
:tuesday
:wednesday
:thursday
:friday
:saturday
:sunday
call_twice_in_a_row: bool

If true and max_retry_attempts >= 2, attempt #2 fires immediately (skipping retry_delay_seconds) when attempt #1 didn't reach a human. Calling-window/allowed-days checks still apply. Only affects the 1→2 transition. Default: false.

calling_windows: Array[{ 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: Integer

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

exclusiveMinimum0
maximum9007199254740991
max_retry_attempts: Integer

Maximum number of call retry attempts. Default: 3.

exclusiveMinimum0
maximum9007199254740991
timezone: 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'.

calls_count: Float

The number of call attempts made.

campaign: { id, name}
id: String
name: String
created_at: untyped

The time the call order was created.

direction: :inbound | :outbound

Whether the call is inbound or outbound.

One of the following:
:inbound
:outbound
first_sentence_delay_ms: Integer

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

minimum-9007199254740991
maximum9007199254740991
from_phone_number: String

The phone number that made the call. Formatted in E.164 format. Example: +1234567890

is_cancelled: bool

DEPRECATED: Whether the call has been cancelled. This is derived from status. Use status instead.

is_completed: bool

DEPRECATED: Whether the call has completed. This is derived from status. Use status instead.

last_call_attempt: { id, answered_at, dial_error, 10 more}

This represent a single call attempt. A call attempt is a single call made to the phone number.

id: String

The ID of the call attempt.

answered_at: untyped

The time the call was answered.

dial_error: :number_non_attributed | :too_many_calls | :busy | 5 more

The SIP error that occurred.

One of the following:
:number_non_attributed
:too_many_calls
:busy
:temporarily_unavailable
:no_answer
:no_international_permission
:precondition_failed
:non_classified_error
ended_at: untyped

The time the call ended.

phone_number: String

The phone number that was called. Formatted in E.164 format. Example: +1234567890

recording_url: String

The URL of the audio recording of the call.

result: :IVR | :voicemail | :human | 2 more
One of the following:
:IVR
:voicemail
:human
:unknown
:"ios-screening-filter"
started_at: untyped

The time the call started.

status: :queued | :ringing | :ongoing | 2 more

The status of the call attempt.

One of the following:
:queued
:ringing
:ongoing
:completed
:error
end_reason: String

Reason for ending the call when ended_by is 'agent'. E.g. 'tool_end_call', 'voicemail', 'transfer', 'ivr_no_navigate'.

ended_by: :agent | :user | :system

Who ended the call: 'agent' (AI agent), 'user' (caller/callee hung up), or 'system' (e.g. max duration limit).

One of the following:
:agent
:user
:system
structured_output: Hash[Symbol, untyped]

The data extracted from the call, using the structured output config from the parent call object.

transcript: Array[{ content, role, tool_arguments, 3 more}]

The transcript of the call.

content: String
role: :user | :assistant | :tool
One of the following:
:user
:assistant
:tool
tool_arguments: Hash[Symbol, untyped] | String
One of the following:
Hash[Symbol, untyped]
String
tool_is_error: bool
tool_name: String
tool_output: String
llm_model: { name, type} | { openrouter_model_id, openrouter_provider, type} | { api_key, api_url, model_name, type} | { provider, realtime_model_id, type, realtime_voice_id}
One of the following:
class UnionMember0 { name, type }
name: :"gpt-4.1" | :"ministral-3-8b-instruct"
One of the following:
:"gpt-4.1"
:"ministral-3-8b-instruct"
type: :"dedicated-instance"
class UnionMember1 { 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.

class UnionMember2 { api_key, api_url, model_name, type }
api_key: String

API key sent as Bearer token to the custom endpoint.

minLength1
api_url: String

Base URL for the OpenAI-compatible API, e.g. https://api.together.xyz/v1

formaturi
model_name: String

Model name as expected by the provider, e.g. meta-llama/llama-3-70b

minLength1
type: :custom

OpenAI-compatible chat completions API (bring your own endpoint and key).

class UnionMember3 { provider, realtime_model_id, type, realtime_voice_id }
provider: :openai | :google

The provider to use from Realtime. eg: openai, google.

One of the following:
:openai
:google
realtime_model_id: String

The model ID to use from Realtime. eg: gpt-4.1

type: :realtime

Use a model from Realtime.

realtime_voice_id: String

Output voice for the realtime provider (e.g. OpenAI: marin; Gemini: Puck).

minLength1
metadata: Hash[Symbol, String]

Metadata stored with the call.

organization_id: String

The ID of the organization that owns the call.

prompt_variables: Hash[Symbol, String]

Variables used to interpolate the prompt.

scheduled_at: untyped

The time the call order is scheduled to start.

status: :initializing | :queued_for_calling | :calling | 4 more

The status of the call.

One of the following:
:initializing
:queued_for_calling
:calling
:scheduled
:completed
:cancelled
:errored
to_phone_number: String

The phone number that received the call. Formatted in E.164 format. Example: +1234567890

updated_at: untyped

The time the call order was last updated (any state change, retry, or analysis result).

outcome: :not_interested | :interested | :completed | 3 more

Business outcome of the call. Null if not computed or no transcript.

One of the following:
:not_interested
:interested
:completed
:requested_callback_later
:requested_callback_new_number
:do_not_contact
outcome_summary: String

LLM explanation for the outcome, when outcome was computed from the transcript.

Place a call

require "revox"

revox = Revox::Client.new(api_key: "My API Key")

call = revox.call.create(phone_number: "phone_number")

puts(call)
{
  "call": {
    "id": "id",
    "assistant": {
      "id": "id",
      "after_call_sms_prompt": "after_call_sms_prompt",
      "background_sound": "audio/office.ogg",
      "background_sound_volume": 0,
      "calendly": {
        "connection_id": "connection_id",
        "event_type_id": "event_type_id"
      },
      "call_retry_config": {
        "allowed_days": [
          "monday"
        ],
        "call_twice_in_a_row": true,
        "calling_windows": [
          {
            "calling_window_end_time": "calling_window_end_time",
            "calling_window_start_time": "calling_window_start_time",
            "retry_delay_seconds": 1
          }
        ],
        "max_retry_attempts": 1,
        "timezone": "timezone"
      },
      "created_at": {},
      "custom_tools": [
        {
          "body_template": "body_template",
          "description": "x",
          "headers": [
            {
              "key": "x",
              "value": "value"
            }
          ],
          "input_schema": [
            {
              "name": "x",
              "required": true,
              "type": "string",
              "description": "description",
              "enum_options": [
                "string"
              ]
            }
          ],
          "method": "GET",
          "name": "name",
          "query_params": [
            {
              "key": "x",
              "value": "value"
            }
          ],
          "url": "x"
        }
      ],
      "email_notification_address": "dev@stainless.com",
      "email_notification_outcomes": [
        "not_interested"
      ],
      "end_of_call_sentence": "end_of_call_sentence",
      "first_sentence": "first_sentence",
      "first_sentence_delay_ms": -9007199254740991,
      "first_sentence_mode": "generated",
      "from_phone_number": "from_phone_number",
      "human_transfer_mode": "warm",
      "ivr_navigation_enabled": true,
      "llm_model": {
        "name": "gpt-4.1",
        "type": "dedicated-instance"
      },
      "max_call_duration_secs": 0,
      "max_duration_end_message": "max_duration_end_message",
      "name": "name",
      "organization_id": "organization_id",
      "prompt": "prompt",
      "sms_enabled": true,
      "sms_template": "sms_template",
      "structured_output_config": [
        {
          "name": "x",
          "required": true,
          "type": "string",
          "description": "description",
          "enum_options": [
            "string"
          ]
        }
      ],
      "structured_output_prompt": "structured_output_prompt",
      "thinking_sound": "city-ambience.ogg",
      "thinking_sound_probability": 0,
      "thinking_sound_volume": 0,
      "transfer_phone_number": "transfer_phone_number",
      "updated_at": {},
      "voice": {
        "id": "x",
        "provider": "cartesia",
        "speed": 0.6,
        "volume": 0.5
      },
      "voicemail_message": "voicemail_message",
      "voicemail_sms_prompt": "voicemail_sms_prompt",
      "warm_transfer_summary_instructions": "warm_transfer_summary_instructions",
      "webhook_url": "webhook_url",
      "faq_items": [
        {
          "answer": "answer",
          "question": "question",
          "id": "id",
          "needs_human_answer": true,
          "source": "human"
        }
      ],
      "pending_faq_count": 0
    },
    "call_attempts": [
      {
        "id": "id",
        "answered_at": {},
        "dial_error": "number_non_attributed",
        "ended_at": {},
        "phone_number": "phone_number",
        "recording_url": "recording_url",
        "result": "IVR",
        "started_at": {},
        "status": "queued",
        "end_reason": "end_reason",
        "ended_by": "agent",
        "structured_output": {
          "foo": "bar"
        },
        "transcript": [
          {
            "content": "content",
            "role": "user",
            "tool_arguments": {
              "foo": "bar"
            },
            "tool_is_error": true,
            "tool_name": "tool_name",
            "tool_output": "tool_output"
          }
        ]
      }
    ],
    "call_retry_config": {
      "allowed_days": [
        "monday"
      ],
      "call_twice_in_a_row": true,
      "calling_windows": [
        {
          "calling_window_end_time": "calling_window_end_time",
          "calling_window_start_time": "calling_window_start_time",
          "retry_delay_seconds": 1
        }
      ],
      "max_retry_attempts": 1,
      "timezone": "timezone"
    },
    "calls_count": 0,
    "campaign": {
      "id": "id",
      "name": "name"
    },
    "created_at": {},
    "direction": "inbound",
    "first_sentence_delay_ms": -9007199254740991,
    "from_phone_number": "from_phone_number",
    "is_cancelled": true,
    "is_completed": true,
    "last_call_attempt": {
      "id": "id",
      "answered_at": {},
      "dial_error": "number_non_attributed",
      "ended_at": {},
      "phone_number": "phone_number",
      "recording_url": "recording_url",
      "result": "IVR",
      "started_at": {},
      "status": "queued",
      "end_reason": "end_reason",
      "ended_by": "agent",
      "structured_output": {
        "foo": "bar"
      },
      "transcript": [
        {
          "content": "content",
          "role": "user",
          "tool_arguments": {
            "foo": "bar"
          },
          "tool_is_error": true,
          "tool_name": "tool_name",
          "tool_output": "tool_output"
        }
      ]
    },
    "llm_model": {
      "name": "gpt-4.1",
      "type": "dedicated-instance"
    },
    "metadata": {
      "foo": "string"
    },
    "organization_id": "organization_id",
    "prompt_variables": {
      "foo": "string"
    },
    "scheduled_at": {},
    "status": "initializing",
    "to_phone_number": "to_phone_number",
    "updated_at": {},
    "outcome": "not_interested",
    "outcome_summary": "outcome_summary"
  }
}
Returns Examples
{
  "call": {
    "id": "id",
    "assistant": {
      "id": "id",
      "after_call_sms_prompt": "after_call_sms_prompt",
      "background_sound": "audio/office.ogg",
      "background_sound_volume": 0,
      "calendly": {
        "connection_id": "connection_id",
        "event_type_id": "event_type_id"
      },
      "call_retry_config": {
        "allowed_days": [
          "monday"
        ],
        "call_twice_in_a_row": true,
        "calling_windows": [
          {
            "calling_window_end_time": "calling_window_end_time",
            "calling_window_start_time": "calling_window_start_time",
            "retry_delay_seconds": 1
          }
        ],
        "max_retry_attempts": 1,
        "timezone": "timezone"
      },
      "created_at": {},
      "custom_tools": [
        {
          "body_template": "body_template",
          "description": "x",
          "headers": [
            {
              "key": "x",
              "value": "value"
            }
          ],
          "input_schema": [
            {
              "name": "x",
              "required": true,
              "type": "string",
              "description": "description",
              "enum_options": [
                "string"
              ]
            }
          ],
          "method": "GET",
          "name": "name",
          "query_params": [
            {
              "key": "x",
              "value": "value"
            }
          ],
          "url": "x"
        }
      ],
      "email_notification_address": "dev@stainless.com",
      "email_notification_outcomes": [
        "not_interested"
      ],
      "end_of_call_sentence": "end_of_call_sentence",
      "first_sentence": "first_sentence",
      "first_sentence_delay_ms": -9007199254740991,
      "first_sentence_mode": "generated",
      "from_phone_number": "from_phone_number",
      "human_transfer_mode": "warm",
      "ivr_navigation_enabled": true,
      "llm_model": {
        "name": "gpt-4.1",
        "type": "dedicated-instance"
      },
      "max_call_duration_secs": 0,
      "max_duration_end_message": "max_duration_end_message",
      "name": "name",
      "organization_id": "organization_id",
      "prompt": "prompt",
      "sms_enabled": true,
      "sms_template": "sms_template",
      "structured_output_config": [
        {
          "name": "x",
          "required": true,
          "type": "string",
          "description": "description",
          "enum_options": [
            "string"
          ]
        }
      ],
      "structured_output_prompt": "structured_output_prompt",
      "thinking_sound": "city-ambience.ogg",
      "thinking_sound_probability": 0,
      "thinking_sound_volume": 0,
      "transfer_phone_number": "transfer_phone_number",
      "updated_at": {},
      "voice": {
        "id": "x",
        "provider": "cartesia",
        "speed": 0.6,
        "volume": 0.5
      },
      "voicemail_message": "voicemail_message",
      "voicemail_sms_prompt": "voicemail_sms_prompt",
      "warm_transfer_summary_instructions": "warm_transfer_summary_instructions",
      "webhook_url": "webhook_url",
      "faq_items": [
        {
          "answer": "answer",
          "question": "question",
          "id": "id",
          "needs_human_answer": true,
          "source": "human"
        }
      ],
      "pending_faq_count": 0
    },
    "call_attempts": [
      {
        "id": "id",
        "answered_at": {},
        "dial_error": "number_non_attributed",
        "ended_at": {},
        "phone_number": "phone_number",
        "recording_url": "recording_url",
        "result": "IVR",
        "started_at": {},
        "status": "queued",
        "end_reason": "end_reason",
        "ended_by": "agent",
        "structured_output": {
          "foo": "bar"
        },
        "transcript": [
          {
            "content": "content",
            "role": "user",
            "tool_arguments": {
              "foo": "bar"
            },
            "tool_is_error": true,
            "tool_name": "tool_name",
            "tool_output": "tool_output"
          }
        ]
      }
    ],
    "call_retry_config": {
      "allowed_days": [
        "monday"
      ],
      "call_twice_in_a_row": true,
      "calling_windows": [
        {
          "calling_window_end_time": "calling_window_end_time",
          "calling_window_start_time": "calling_window_start_time",
          "retry_delay_seconds": 1
        }
      ],
      "max_retry_attempts": 1,
      "timezone": "timezone"
    },
    "calls_count": 0,
    "campaign": {
      "id": "id",
      "name": "name"
    },
    "created_at": {},
    "direction": "inbound",
    "first_sentence_delay_ms": -9007199254740991,
    "from_phone_number": "from_phone_number",
    "is_cancelled": true,
    "is_completed": true,
    "last_call_attempt": {
      "id": "id",
      "answered_at": {},
      "dial_error": "number_non_attributed",
      "ended_at": {},
      "phone_number": "phone_number",
      "recording_url": "recording_url",
      "result": "IVR",
      "started_at": {},
      "status": "queued",
      "end_reason": "end_reason",
      "ended_by": "agent",
      "structured_output": {
        "foo": "bar"
      },
      "transcript": [
        {
          "content": "content",
          "role": "user",
          "tool_arguments": {
            "foo": "bar"
          },
          "tool_is_error": true,
          "tool_name": "tool_name",
          "tool_output": "tool_output"
        }
      ]
    },
    "llm_model": {
      "name": "gpt-4.1",
      "type": "dedicated-instance"
    },
    "metadata": {
      "foo": "string"
    },
    "organization_id": "organization_id",
    "prompt_variables": {
      "foo": "string"
    },
    "scheduled_at": {},
    "status": "initializing",
    "to_phone_number": "to_phone_number",
    "updated_at": {},
    "outcome": "not_interested",
    "outcome_summary": "outcome_summary"
  }
}