Assistants

Create Assistant

Headers

AuthorizationstringRequired

Bearer authentication of the form Bearer <token>, where token is your auth token.

Request

This endpoint expects an object.
transcriberobjectOptional
These are the options for the assistant's transcriber.
modelobjectOptional
These are the options for the assistant's LLM.
voiceobjectOptional
These are the options for the assistant's voice.
firstMessagestringOptional

This is the first message that the assistant will say. This can also be a URL to a containerized audio file (mp3, wav, etc.).

If unspecified, assistant will wait for user to speak and use the model to respond once they speak.

firstMessageInterruptionsEnabledbooleanOptionalDefaults to false
firstMessageModeenumOptional
This is the mode for the first message. Default is 'assistant-speaks-first'. Use: - 'assistant-speaks-first' to have the assistant speak first. - 'assistant-waits-for-user' to have the assistant wait for the user to speak first. - 'assistant-speaks-first-with-model-generated-message' to have the assistant speak first with a message generated by the model based on the conversation state. (`assistant.model.messages` at call start, `call.messages` at squad transfer points). @default 'assistant-speaks-first'
Allowed values:
voicemailDetectionobjectOptional
These are the settings to configure or disable voicemail detection. Alternatively, voicemail detection can be configured using the model.tools=[VoicemailTool]. This uses Twilio's built-in detection while the VoicemailTool relies on the model to detect if a voicemail was reached. You can use neither of them, one of them, or both of them. By default, Twilio built-in detection is enabled while VoicemailTool is not.
clientMessagesenumOptional

These are the messages that will be sent to your Client SDKs. Default is conversation-update,function-call,hang,model-output,speech-update,status-update,transfer-update,transcript,tool-calls,user-interrupted,voice-input,workflow.node.started. You can check the shape of the messages in ClientMessage schema.

serverMessagesenumOptional

These are the messages that will be sent to your Server URL. Default is conversation-update,end-of-call-report,function-call,hang,speech-update,status-update,tool-calls,transfer-destination-request,handoff-destination-request,user-interrupted. You can check the shape of the messages in ServerMessage schema.

maxDurationSecondsdoubleOptional>=10<=43200

This is the maximum number of seconds that the call will last. When the call reaches this duration, it will be ended.

@default 600 (10 minutes)

backgroundSoundenum or stringOptional
This is the background sound in the call. Default for phone calls is 'office' and default for web calls is 'off'. You can also provide a custom sound by providing a URL to an audio file.
modelOutputInMessagesEnabledbooleanOptional

This determines whether the model’s output is used in conversation history rather than the transcription of assistant’s speech.

Default false while in beta.

@default false

transportConfigurationslist of objectsOptional
These are the configurations to be passed to the transport providers of assistant's calls, like Twilio. You can store multiple configurations for different transport providers. For a call, only the configuration matching the call transport provider is used.
observabilityPlanobjectOptional
This is the plan for observability of assistant's calls. Currently, only Langfuse is supported.
credentialslist of objectsOptional
These are dynamic credentials that will be used for the assistant calls. By default, all the credentials are available for use in the call but you can supplement an additional credentials using this. Dynamic credentials override existing credentials.
hookslist of objectsOptional
This is a set of actions that will be performed on certain events.
namestringOptional<=40 characters
This is the name of the assistant. This is required when you want to transfer between assistants in a call.
voicemailMessagestringOptional<=1000 characters
This is the message that the assistant will say if the call is forwarded to voicemail. If unspecified, it will hang up.
endCallMessagestringOptional<=1000 characters
This is the message that the assistant will say if it ends the call. If unspecified, it will hang up without saying anything.
endCallPhraseslist of stringsOptional
This list contains phrases that, if spoken by the assistant, will trigger the call to be hung up. Case insensitive.
compliancePlanobjectOptional
metadataobjectOptional
This is for metadata you want to store on the assistant.
backgroundSpeechDenoisingPlanobjectOptional
This enables filtering of noise and background speech while the user is talking. Features: - Smart denoising using Krisp - Fourier denoising Smart denoising can be combined with or used independently of Fourier denoising. Order of precedence: - Smart denoising - Fourier denoising
analysisPlanobjectOptional

This is the plan for analysis of assistant’s calls. Stored in call.analysis.

artifactPlanobjectOptional

This is the plan for artifacts generated during assistant’s calls. Stored in call.artifact.

startSpeakingPlanobjectOptional
This is the plan for when the assistant should start talking. You should configure this if you're running into these issues: - The assistant is too slow to start talking after the customer is done speaking. - The assistant is too fast to start talking after the customer is done speaking. - The assistant is so fast that it's actually interrupting the customer.
stopSpeakingPlanobjectOptional
This is the plan for when assistant should stop talking on customer interruption. You should configure this if you're running into these issues: - The assistant is too slow to recognize customer's interruption. - The assistant is too fast to recognize customer's interruption. - The assistant is getting interrupted by phrases that are just acknowledgments. - The assistant is getting interrupted by background noises. - The assistant is not properly stopping -- it starts talking right after getting interrupted.
monitorPlanobjectOptional
This is the plan for real-time monitoring of the assistant's calls. Usage: - To enable live listening of the assistant's calls, set `monitorPlan.listenEnabled` to `true`. - To enable live control of the assistant's calls, set `monitorPlan.controlEnabled` to `true`.
credentialIdslist of stringsOptional
These are the credentials that will be used for the assistant calls. By default, all the credentials are available for use in the call but you can provide a subset using this.
serverobjectOptional

This is where Vapi will send webhooks. You can find all webhooks available along with their shape in ServerMessage schema.

The order of precedence is:

  1. assistant.server.url
  2. phoneNumber.serverUrl
  3. org.serverUrl
keypadInputPlanobjectOptional

Response

idstring
This is the unique identifier for the assistant.
orgIdstring
This is the unique identifier for the org that this assistant belongs to.
createdAtstringformat: "date-time"

This is the ISO 8601 date-time string of when the assistant was created.

updatedAtstringformat: "date-time"

This is the ISO 8601 date-time string of when the assistant was last updated.

transcriberobject or null
These are the options for the assistant's transcriber.
modelobject or null
These are the options for the assistant's LLM.
voiceobject or null
These are the options for the assistant's voice.
firstMessagestring or null

This is the first message that the assistant will say. This can also be a URL to a containerized audio file (mp3, wav, etc.).

If unspecified, assistant will wait for user to speak and use the model to respond once they speak.

firstMessageInterruptionsEnabledboolean or nullDefaults to false
firstMessageModeenum or null
This is the mode for the first message. Default is 'assistant-speaks-first'. Use: - 'assistant-speaks-first' to have the assistant speak first. - 'assistant-waits-for-user' to have the assistant wait for the user to speak first. - 'assistant-speaks-first-with-model-generated-message' to have the assistant speak first with a message generated by the model based on the conversation state. (`assistant.model.messages` at call start, `call.messages` at squad transfer points). @default 'assistant-speaks-first'
Allowed values:
voicemailDetectionobject or null
These are the settings to configure or disable voicemail detection. Alternatively, voicemail detection can be configured using the model.tools=[VoicemailTool]. This uses Twilio's built-in detection while the VoicemailTool relies on the model to detect if a voicemail was reached. You can use neither of them, one of them, or both of them. By default, Twilio built-in detection is enabled while VoicemailTool is not.
clientMessagesenum or null

These are the messages that will be sent to your Client SDKs. Default is conversation-update,function-call,hang,model-output,speech-update,status-update,transfer-update,transcript,tool-calls,user-interrupted,voice-input,workflow.node.started. You can check the shape of the messages in ClientMessage schema.

serverMessagesenum or null

These are the messages that will be sent to your Server URL. Default is conversation-update,end-of-call-report,function-call,hang,speech-update,status-update,tool-calls,transfer-destination-request,handoff-destination-request,user-interrupted. You can check the shape of the messages in ServerMessage schema.

maxDurationSecondsdouble or null>=10<=43200

This is the maximum number of seconds that the call will last. When the call reaches this duration, it will be ended.

@default 600 (10 minutes)

backgroundSoundenum or string or null
This is the background sound in the call. Default for phone calls is 'office' and default for web calls is 'off'. You can also provide a custom sound by providing a URL to an audio file.
modelOutputInMessagesEnabledboolean or null

This determines whether the model’s output is used in conversation history rather than the transcription of assistant’s speech.

Default false while in beta.

@default false

transportConfigurationslist of objects or null
These are the configurations to be passed to the transport providers of assistant's calls, like Twilio. You can store multiple configurations for different transport providers. For a call, only the configuration matching the call transport provider is used.
observabilityPlanobject or null
This is the plan for observability of assistant's calls. Currently, only Langfuse is supported.
credentialslist of objects or null
These are dynamic credentials that will be used for the assistant calls. By default, all the credentials are available for use in the call but you can supplement an additional credentials using this. Dynamic credentials override existing credentials.
hookslist of objects or null
This is a set of actions that will be performed on certain events.
namestring or null<=40 characters
This is the name of the assistant. This is required when you want to transfer between assistants in a call.
voicemailMessagestring or null<=1000 characters
This is the message that the assistant will say if the call is forwarded to voicemail. If unspecified, it will hang up.
endCallMessagestring or null<=1000 characters
This is the message that the assistant will say if it ends the call. If unspecified, it will hang up without saying anything.
endCallPhraseslist of strings or null
This list contains phrases that, if spoken by the assistant, will trigger the call to be hung up. Case insensitive.
compliancePlanobject or null
metadataobject or null
This is for metadata you want to store on the assistant.
backgroundSpeechDenoisingPlanobject or null
This enables filtering of noise and background speech while the user is talking. Features: - Smart denoising using Krisp - Fourier denoising Smart denoising can be combined with or used independently of Fourier denoising. Order of precedence: - Smart denoising - Fourier denoising
analysisPlanobject or null

This is the plan for analysis of assistant’s calls. Stored in call.analysis.

artifactPlanobject or null

This is the plan for artifacts generated during assistant’s calls. Stored in call.artifact.

startSpeakingPlanobject or null
This is the plan for when the assistant should start talking. You should configure this if you're running into these issues: - The assistant is too slow to start talking after the customer is done speaking. - The assistant is too fast to start talking after the customer is done speaking. - The assistant is so fast that it's actually interrupting the customer.
stopSpeakingPlanobject or null
This is the plan for when assistant should stop talking on customer interruption. You should configure this if you're running into these issues: - The assistant is too slow to recognize customer's interruption. - The assistant is too fast to recognize customer's interruption. - The assistant is getting interrupted by phrases that are just acknowledgments. - The assistant is getting interrupted by background noises. - The assistant is not properly stopping -- it starts talking right after getting interrupted.
monitorPlanobject or null
This is the plan for real-time monitoring of the assistant's calls. Usage: - To enable live listening of the assistant's calls, set `monitorPlan.listenEnabled` to `true`. - To enable live control of the assistant's calls, set `monitorPlan.controlEnabled` to `true`.
credentialIdslist of strings or null
These are the credentials that will be used for the assistant calls. By default, all the credentials are available for use in the call but you can provide a subset using this.
serverobject or null

This is where Vapi will send webhooks. You can find all webhooks available along with their shape in ServerMessage schema.

The order of precedence is:

  1. assistant.server.url
  2. phoneNumber.serverUrl
  3. org.serverUrl
keypadInputPlanobject or null