> For the complete documentation index, see [llms.txt](https://docs.welkinhealth.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.welkinhealth.com/api-reference/communication-api.md).

# Communication API

## Create communication id SMS

> Step 1 of sending a message: generates a \`communicationId\` for the given channel and patient contact. No message is sent and no resource is created by this call alone — pass the returned \`communicationId\` to \`POST /{communicationId}/messages\` to actually send it. Confirmed against \`welikan-communication-proxy-service\` (\`CommunicationController.createCommunicationId\`).

```json
{"openapi":"3.0.3","info":{"title":"Welkin Health API","version":"1.0.0"},"tags":[{"name":"Communication API","description":""}],"servers":[{"url":"https://api.live.welkincloud.io","description":"Welkin Health production API"}],"security":[{"bearerAuth":[]}],"components":{"securitySchemes":{"bearerAuth":{"type":"http","scheme":"bearer","description":"Bearer token obtained from `POST /{tenantName}/admin/api_clients/{clientName}`. Valid for 60 minutes."}},"parameters":{"TenantName":{"name":"tenantName","in":"path","required":true,"description":"Your organization (tenant) name, e.g. `acme-health`","schema":{"type":"string"}},"InstanceName":{"name":"instanceName","in":"path","required":true,"description":"Your environment name: `live`, `sandbox`, or a custom name","schema":{"type":"string"}}},"schemas":{"CreateCommunicationIdResponse":{"type":"object","properties":{"communicationId":{"type":"string","description":"Opaque token to pass to the send-message endpoint. Not a persisted resource — it is a Base64 encoding of the request above, decoded server-side on the next call."}}},"CreateCommunicationIdRequest":{"type":"object","required":["channel","patientContactId"],"properties":{"channel":{"$ref":"#/components/schemas/Channel"},"patientContactId":{"type":"string","format":"uuid"},"instancePhoneId":{"type":"string","format":"uuid","description":"Required for SMS/VOICE_CALL if patientContactPhoneNumber is not the default."},"patientContactPhoneNumber":{"type":"string","description":"E.164 format. If omitted for SMS/VOICE_CALL, the patient contact's default phone is used."}}},"Channel":{"type":"string","enum":["SMS","EMAIL","VOICE_CALL"]}},"responses":{"BadRequest":{"description":"Bad request — the request could not be understood or was missing required parameters."},"Unauthorized":{"description":"Unauthorized — the Bearer token is missing, expired, or invalid."},"Forbidden":{"description":"Forbidden — the API client role does not have permission for this resource. Check the role and security policy in Admin."},"NotFound":{"description":"Not found — the requested resource does not exist."},"TooManyRequests":{"description":"Too many requests — rate limit exceeded. Implement exponential backoff."},"InternalError":{"description":"Internal server error."}}},"paths":{"/{tenantName}/{instanceName}/communications":{"post":{"summary":"Create communication id SMS","tags":["Communication API"],"operationId":"Create_communication_id_SMS","parameters":[{"$ref":"#/components/parameters/TenantName"},{"$ref":"#/components/parameters/InstanceName"}],"responses":{"200":{"description":"Communication ID generated (no resource is persisted).","content":{"application/json":{"schema":{"$ref":"#/components/schemas/CreateCommunicationIdResponse"}}}},"400":{"$ref":"#/components/responses/BadRequest"},"401":{"$ref":"#/components/responses/Unauthorized"},"403":{"$ref":"#/components/responses/Forbidden"},"404":{"$ref":"#/components/responses/NotFound"},"429":{"$ref":"#/components/responses/TooManyRequests"},"500":{"$ref":"#/components/responses/InternalError"}},"description":"Step 1 of sending a message: generates a `communicationId` for the given channel and patient contact. No message is sent and no resource is created by this call alone — pass the returned `communicationId` to `POST /{communicationId}/messages` to actually send it. Confirmed against `welikan-communication-proxy-service` (`CommunicationController.createCommunicationId`).","requestBody":{"required":true,"content":{"application/json":{"schema":{"$ref":"#/components/schemas/CreateCommunicationIdRequest"}}}}}}}}
```

## Send message

> Step 2 of sending a message: sends the actual message on the channel established by the \`communicationId\`. Request shape depends on that channel: SMS needs \`message\`; Email needs \`message\` + \`subject\` (+ optional \`secure\`); Voice Call takes only \`recorded\`. For SMS/Email, use \`multipart/form-data\` instead to attach files via \`attachmentsAsFiles\`. The response is the created SMS/Email/Voice Call record from the underlying resource, matching the corresponding resource schema in the SMS/Email/Calls sections of this API. Confirmed against \`welikan-communication-proxy-service\` (\`MessageController.createAndSendMessage\`), which proxies to the corresponding \`welikan\` monolith endpoint.

```json
{"openapi":"3.0.3","info":{"title":"Welkin Health API","version":"1.0.0"},"tags":[{"name":"Communication API","description":""}],"servers":[{"url":"https://api.live.welkincloud.io","description":"Welkin Health production API"}],"security":[{"bearerAuth":[]}],"components":{"securitySchemes":{"bearerAuth":{"type":"http","scheme":"bearer","description":"Bearer token obtained from `POST /{tenantName}/admin/api_clients/{clientName}`. Valid for 60 minutes."}},"parameters":{"TenantName":{"name":"tenantName","in":"path","required":true,"description":"Your organization (tenant) name, e.g. `acme-health`","schema":{"type":"string"}},"InstanceName":{"name":"instanceName","in":"path","required":true,"description":"Your environment name: `live`, `sandbox`, or a custom name","schema":{"type":"string"}}},"schemas":{"SmsMessageRequest":{"type":"object","required":["message"],"properties":{"message":{"type":"string","maxLength":1600},"attachmentsFromTemplate":{"type":"array","items":{"$ref":"#/components/schemas/File"}}}},"File":{"type":"object","properties":{"id":{"type":"string","format":"uuid"},"originalName":{"type":"string"},"size":{"type":"integer","description":"Bytes"},"contentType":{"type":"string"},"storageKey":{"type":"string"}}},"EmailMessageRequest":{"type":"object","required":["message","subject"],"properties":{"message":{"type":"string"},"subject":{"type":"string"},"secure":{"type":"boolean","default":false},"attachmentsFromTemplate":{"type":"array","items":{"$ref":"#/components/schemas/File"}}}},"VoiceCallMessageRequest":{"type":"object","properties":{"recorded":{"type":"boolean","default":false}}},"SmsMessageMultipartRequest":{"type":"object","required":["message"],"properties":{"message":{"type":"string"},"attachmentsAsFiles":{"type":"array","items":{"type":"string","format":"binary"}}}},"EmailMessageMultipartRequest":{"type":"object","required":["message","subject"],"properties":{"message":{"type":"string"},"subject":{"type":"string"},"secure":{"type":"boolean","default":false},"attachmentsAsFiles":{"type":"array","items":{"type":"string","format":"binary"}}}},"Sms":{"type":"object","required":["sender","message"],"properties":{"id":{"type":"string","format":"uuid","readOnly":true},"createdAt":{"type":"string","format":"date-time","readOnly":true},"updatedAt":{"type":"string","format":"date-time","readOnly":true},"createdBy":{"type":"string","format":"uuid","readOnly":true},"updatedBy":{"type":"string","format":"uuid","readOnly":true},"createdByName":{"type":"string","readOnly":true},"updatedByName":{"type":"string","readOnly":true},"sendNow":{"type":"boolean"},"sentAt":{"type":"string","format":"date-time","nullable":true},"receivedAt":{"type":"string","format":"date-time","nullable":true},"deletedAt":{"type":"string","format":"date-time","nullable":true},"date":{"type":"string","format":"date-time","nullable":true},"careTeam":{"type":"string","nullable":true},"patientInfo":{"type":"string","nullable":true},"sender":{"type":"string","format":"uuid"},"senderType":{"$ref":"#/components/schemas/ActorType"},"senderName":{"type":"string","nullable":true},"from":{"type":"string","nullable":true},"receiver":{"type":"string","format":"uuid","nullable":true},"receiverType":{"$ref":"#/components/schemas/ActorType"},"receiverName":{"type":"string","nullable":true},"to":{"type":"string","nullable":true},"direction":{"$ref":"#/components/schemas/Direction"},"externalId":{"type":"string","nullable":true},"starred":{"type":"boolean"},"errorMessage":{"type":"string","nullable":true},"assignedBy":{"type":"string","format":"uuid","readOnly":true,"nullable":true},"assignedByName":{"type":"string","readOnly":true,"nullable":true},"hasHistory":{"type":"boolean","readOnly":true},"unrecognized":{"type":"boolean","readOnly":true},"message":{"type":"string","maxLength":1600},"parts":{"type":"integer","readOnly":true},"status":{"$ref":"#/components/schemas/SmsStatus"},"messageType":{"$ref":"#/components/schemas/MessageType","default":"CARE_TEAM"},"phoneId":{"type":"string","format":"uuid"},"attachments":{"type":"array","items":{"$ref":"#/components/schemas/File"},"readOnly":true},"attachmentsFromTemplate":{"type":"array","items":{"$ref":"#/components/schemas/File"}},"skipEvent":{"type":"boolean"}}},"ActorType":{"type":"string","enum":["CS_TOOL_CLIENT","USER","API_CLIENT","PATIENT","CONTACT","SYSTEM","WEBHOOK","INTERNAL_SERVICE","ANONYMOUS","UNRECOGNISED"]},"Direction":{"type":"string","enum":["OUT","IN"]},"SmsStatus":{"type":"string","enum":["SCHEDULED","ACCEPTED","SENT","RECEIVED","DELIVERED","UNDELIVERED","FAILED","UNRECOGNISED","DELETED"]},"MessageType":{"type":"string","enum":["CARE_TEAM","SYSTEM_TO_USER","SYSTEM_TO_PATIENT"]},"Email":{"type":"object","required":["sender","body"],"properties":{"id":{"type":"string","format":"uuid","readOnly":true},"createdAt":{"type":"string","format":"date-time","readOnly":true},"updatedAt":{"type":"string","format":"date-time","readOnly":true},"createdBy":{"type":"string","format":"uuid","readOnly":true},"updatedBy":{"type":"string","format":"uuid","readOnly":true},"createdByName":{"type":"string","readOnly":true},"updatedByName":{"type":"string","readOnly":true},"sendNow":{"type":"boolean"},"sentAt":{"type":"string","format":"date-time","nullable":true},"receivedAt":{"type":"string","format":"date-time","nullable":true},"deletedAt":{"type":"string","format":"date-time","nullable":true},"date":{"type":"string","format":"date-time","nullable":true},"careTeam":{"type":"string","nullable":true},"patientInfo":{"type":"string","nullable":true},"sender":{"type":"string","format":"uuid"},"senderType":{"$ref":"#/components/schemas/ActorType"},"senderName":{"type":"string","nullable":true},"from":{"type":"string","nullable":true},"receiver":{"type":"string","format":"uuid","nullable":true},"receiverType":{"$ref":"#/components/schemas/ActorType"},"receiverName":{"type":"string","nullable":true},"to":{"type":"string","nullable":true},"direction":{"$ref":"#/components/schemas/Direction"},"externalId":{"type":"string","nullable":true},"starred":{"type":"boolean"},"errorMessage":{"type":"string","nullable":true},"assignedBy":{"type":"string","format":"uuid","readOnly":true,"nullable":true},"assignedByName":{"type":"string","readOnly":true,"nullable":true},"hasHistory":{"type":"boolean","readOnly":true},"unrecognized":{"type":"boolean","readOnly":true},"subject":{"type":"string","nullable":true},"body":{"type":"string"},"emailEditorJson":{"type":"string","nullable":true},"status":{"$ref":"#/components/schemas/EmailStatus"},"secure":{"type":"boolean","default":false},"attachments":{"type":"array","items":{"$ref":"#/components/schemas/File"},"readOnly":true},"attachmentsFromTemplate":{"type":"array","items":{"$ref":"#/components/schemas/File"}},"bodyAttachments":{"type":"array","items":{"$ref":"#/components/schemas/SignedFile"}},"messageType":{"$ref":"#/components/schemas/MessageType","default":"CARE_TEAM"},"bodyType":{"$ref":"#/components/schemas/EmailBodyType","default":"PLAIN_TEXT"},"inReplyTo":{"type":"string","nullable":true},"messageId":{"type":"string","nullable":true},"skipEvent":{"type":"boolean"}}},"EmailStatus":{"type":"string","enum":["SCHEDULED","ACCEPTED","SENT","DELIVERED","REJECTED","FAILED","UNRECOGNISED","DELETED","CLICKED","OPENED"]},"SignedFile":{"allOf":[{"$ref":"#/components/schemas/File"},{"type":"object","properties":{"url":{"type":"string","format":"uri"},"thumbnailUrl":{"type":"string","format":"uri","nullable":true}}}]},"EmailBodyType":{"type":"string","enum":["PLAIN_TEXT","HTML"]},"VoiceCall":{"type":"object","required":["sender"],"properties":{"id":{"type":"string","format":"uuid","readOnly":true},"createdAt":{"type":"string","format":"date-time","readOnly":true},"updatedAt":{"type":"string","format":"date-time","readOnly":true},"createdBy":{"type":"string","format":"uuid","readOnly":true},"updatedBy":{"type":"string","format":"uuid","readOnly":true},"createdByName":{"type":"string","readOnly":true},"updatedByName":{"type":"string","readOnly":true},"sendNow":{"type":"boolean"},"sentAt":{"type":"string","format":"date-time","nullable":true},"receivedAt":{"type":"string","format":"date-time","nullable":true},"deletedAt":{"type":"string","format":"date-time","nullable":true},"date":{"type":"string","format":"date-time","nullable":true},"careTeam":{"type":"string","nullable":true},"patientInfo":{"type":"string","nullable":true},"sender":{"type":"string","format":"uuid"},"senderType":{"$ref":"#/components/schemas/ActorType"},"senderName":{"type":"string","nullable":true},"from":{"type":"string","nullable":true},"receiver":{"type":"string","format":"uuid","nullable":true},"receiverType":{"$ref":"#/components/schemas/ActorType"},"receiverName":{"type":"string","nullable":true},"to":{"type":"string","nullable":true},"direction":{"$ref":"#/components/schemas/Direction"},"externalId":{"type":"string","nullable":true},"starred":{"type":"boolean"},"errorMessage":{"type":"string","nullable":true},"assignedBy":{"type":"string","format":"uuid","readOnly":true,"nullable":true},"assignedByName":{"type":"string","readOnly":true,"nullable":true},"hasHistory":{"type":"boolean","readOnly":true},"unrecognized":{"type":"boolean","readOnly":true},"childCallSid":{"type":"string","nullable":true},"parentCallStatus":{"$ref":"#/components/schemas/VoiceCallStatus"},"childCallStatus":{"$ref":"#/components/schemas/VoiceCallStatus"},"userPhone":{"type":"string","nullable":true},"parentCallDuration":{"type":"integer","nullable":true},"childCallDuration":{"type":"integer","nullable":true},"recorded":{"type":"boolean"},"recordingDuration":{"type":"integer","nullable":true},"recordingSid":{"type":"string","nullable":true},"recordingUrl":{"type":"string","nullable":true},"recordingFile":{"$ref":"#/components/schemas/File","nullable":true},"phoneId":{"type":"string","format":"uuid","nullable":true}}},"VoiceCallStatus":{"type":"string","enum":["QUEUED","INITIATED","RINGING","IN_PROGRESS","COMPLETED","BUSY","NO_ANSWER","CANCELED","FAILED"]},"CommunicationError":{"type":"object","properties":{"errorCode":{"type":"string","enum":["VALIDATION_ERROR","COMMUNICATION_ID_INVALID_ERROR","CHANNEL_TYPE_INVALID_ERROR","COMMUNICATION_ERROR","GENERIC","UNKNOWN_ERROR"]},"componentType":{"type":"string","nullable":true},"message":{"type":"string"},"details":{"$ref":"#/components/schemas/CommunicationErrorDetails"},"date":{"type":"string","format":"date-time"}}},"CommunicationErrorDetails":{"type":"object","properties":{"fieldName":{"type":"string","nullable":true},"value":{"description":"The offending value, if applicable. Type varies."}}}},"responses":{"Unauthorized":{"description":"Unauthorized — the Bearer token is missing, expired, or invalid."},"Forbidden":{"description":"Forbidden — the API client role does not have permission for this resource. Check the role and security policy in Admin."},"NotFound":{"description":"Not found — the requested resource does not exist."},"TooManyRequests":{"description":"Too many requests — rate limit exceeded. Implement exponential backoff."}}},"paths":{"/{tenantName}/{instanceName}/{communicationId}/messages":{"post":{"summary":"Send message","tags":["Communication API"],"operationId":"Send_Message","parameters":[{"$ref":"#/components/parameters/TenantName"},{"$ref":"#/components/parameters/InstanceName"},{"name":"communicationId","in":"path","required":true,"description":"Opaque token returned by `POST /communications`.","schema":{"type":"string"}}],"description":"Step 2 of sending a message: sends the actual message on the channel established by the `communicationId`. Request shape depends on that channel: SMS needs `message`; Email needs `message` + `subject` (+ optional `secure`); Voice Call takes only `recorded`. For SMS/Email, use `multipart/form-data` instead to attach files via `attachmentsAsFiles`. The response is the created SMS/Email/Voice Call record from the underlying resource, matching the corresponding resource schema in the SMS/Email/Calls sections of this API. Confirmed against `welikan-communication-proxy-service` (`MessageController.createAndSendMessage`), which proxies to the corresponding `welikan` monolith endpoint.","requestBody":{"required":true,"content":{"application/json":{"schema":{"oneOf":[{"$ref":"#/components/schemas/SmsMessageRequest"},{"$ref":"#/components/schemas/EmailMessageRequest"},{"$ref":"#/components/schemas/VoiceCallMessageRequest"}]}},"multipart/form-data":{"schema":{"oneOf":[{"$ref":"#/components/schemas/SmsMessageMultipartRequest"},{"$ref":"#/components/schemas/EmailMessageMultipartRequest"}]}}}},"responses":{"200":{"description":"Message sent — response shape matches the SMS/Email/Voice Call resource for the channel used.","content":{"application/json":{"schema":{"oneOf":[{"$ref":"#/components/schemas/Sms"},{"$ref":"#/components/schemas/Email"},{"$ref":"#/components/schemas/VoiceCall"}]}}}},"400":{"description":"Validation error, invalid communicationId, or invalid channel.","content":{"application/json":{"schema":{"type":"array","items":{"$ref":"#/components/schemas/CommunicationError"}}}}},"401":{"$ref":"#/components/responses/Unauthorized"},"403":{"$ref":"#/components/responses/Forbidden"},"404":{"$ref":"#/components/responses/NotFound"},"429":{"$ref":"#/components/responses/TooManyRequests"},"500":{"description":"Downstream communication error or unexpected failure.","content":{"application/json":{"schema":{"type":"array","items":{"$ref":"#/components/schemas/CommunicationError"}}}}}}}}}}
```


---

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Perform an HTTP GET request on the current page URL with the `ask` query parameter, and the optional `goal` query parameter:

```
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