> ## Documentation Index > Fetch the complete documentation index at: https://developers.telnyx.com/llms.txt > Use this file to discover all available pages before exploring further. # Join a conference > Join an existing call leg to a conference. Issue the Join Conference command with the conference ID in the path and the `call_control_id` of the leg you wish to join to the conference as an attribute. The conference can have up to a certain amount of active participants, as set by the `max_participants` parameter in conference creation request. **Expected Webhooks:** - `conference.participant.joined` - `conference.participant.left` ## OpenAPI ````yaml https://telnyx-openapi-ng.s3.us-east-1.amazonaws.com/call-control/conferences.yml post /conferences/{id}/actions/join openapi: 3.1.0 info: title: Telnyx Conferences API version: 2.0.0 description: API for Conferences. contact: email: support@telnyx.com servers: - url: https://api.telnyx.com/v2 security: - bearerAuth: [] paths: /conferences/{id}/actions/join: post: tags: - Conference Commands summary: Join a conference description: > Join an existing call leg to a conference. Issue the Join Conference command with the conference ID in the path and the `call_control_id` of the leg you wish to join to the conference as an attribute. The conference can have up to a certain amount of active participants, as set by the `max_participants` parameter in conference creation request. **Expected Webhooks:** - `conference.participant.joined` - `conference.participant.left` operationId: JoinConference parameters: - name: id description: Uniquely identifies the conference by id or name in: path required: true schema: type: string requestBody: description: Join Conference request object required: true content: application/json: schema: $ref: '#/components/schemas/JoinConferenceRequest' responses: '200': $ref: '#/components/responses/ConferenceCommandResponse' '401': $ref: '#/components/responses/UnauthorizedResponse' '422': $ref: '#/components/responses/UnprocessableEntityResponse' x-codeSamples: - lang: JavaScript source: |- import Telnyx from 'telnyx'; const client = new Telnyx({ apiKey: process.env['TELNYX_API_KEY'], // This is the default and can be omitted }); const response = await client.conferences.actions.join('id', { call_control_id: 'v3:MdI91X4lWFEs7IgbBEOT9M4AigoY08M0WWZFISt1Yw2axZ_IiE4pqg', }); console.log(response.data); - lang: Python source: |- import os from telnyx import Telnyx client = Telnyx( api_key=os.environ.get("TELNYX_API_KEY"), # This is the default and can be omitted ) response = client.conferences.actions.join( id="id", call_control_id="v3:MdI91X4lWFEs7IgbBEOT9M4AigoY08M0WWZFISt1Yw2axZ_IiE4pqg", ) print(response.data) - lang: Go source: "package main\n\nimport (\n\t\"context\"\n\t\"fmt\"\n\n\t\"github.com/team-telnyx/telnyx-go\"\n\t\"github.com/team-telnyx/telnyx-go/option\"\n)\n\nfunc main() {\n\tclient := telnyx.NewClient(\n\t\toption.WithAPIKey(\"My API Key\"),\n\t)\n\tresponse, err := client.Conferences.Actions.Join(\n\t\tcontext.TODO(),\n\t\t\"id\",\n\t\ttelnyx.ConferenceActionJoinParams{\n\t\t\tCallControlID: \"v3:MdI91X4lWFEs7IgbBEOT9M4AigoY08M0WWZFISt1Yw2axZ_IiE4pqg\",\n\t\t},\n\t)\n\tif err != nil {\n\t\tpanic(err.Error())\n\t}\n\tfmt.Printf(\"%+v\\n\", response.Data)\n}\n" - lang: Java source: |- package com.telnyx.sdk.example; import com.telnyx.sdk.client.TelnyxClient; import com.telnyx.sdk.client.okhttp.TelnyxOkHttpClient; import com.telnyx.sdk.models.conferences.actions.ActionJoinParams; import com.telnyx.sdk.models.conferences.actions.ActionJoinResponse; public final class Main { private Main() {} public static void main(String[] args) { TelnyxClient client = TelnyxOkHttpClient.fromEnv(); ActionJoinParams params = ActionJoinParams.builder() .id("id") .callControlId("v3:MdI91X4lWFEs7IgbBEOT9M4AigoY08M0WWZFISt1Yw2axZ_IiE4pqg") .build(); ActionJoinResponse response = client.conferences().actions().join(params); } } - lang: Ruby source: |- require "telnyx" telnyx = Telnyx::Client.new(api_key: "My API Key") response = telnyx.conferences.actions.join( "id", call_control_id: "v3:MdI91X4lWFEs7IgbBEOT9M4AigoY08M0WWZFISt1Yw2axZ_IiE4pqg" ) puts(response) - lang: PHP source: >- conferences->actions->join( 'id', callControlID: 'v3:MdI91X4lWFEs7IgbBEOT9M4AigoY08M0WWZFISt1Yw2axZ_IiE4pqg', beepEnabled: 'always', clientState: 'aGF2ZSBhIG5pY2UgZGF5ID1d', commandID: '891510ac-f3e4-11e8-af5b-de00688a4901', endConferenceOnExit: true, hold: true, holdAudioURL: 'http://www.example.com/audio.wav', holdMediaName: 'my_media_uploaded_to_media_storage_api', mute: true, region: 'US', softEndConferenceOnExit: true, startConferenceOnEnter: true, supervisorRole: 'whisper', whisperCallControlIDs: [ 'v2:Sg1xxxQ_U3ixxxyXT_VDNI3xxxazZdg6Vxxxs4-GNYxxxVaJPOhFMRQ', 'v2:qqpb0mmvd-ovhhBr0BUQQn0fld5jIboaaX3-De0DkqXHzbf8d75xkw', ], ); var_dump($response); } catch (APIException $e) { echo $e->getMessage(); } - lang: CLI source: |- telnyx conferences:actions join \ --api-key 'My API Key' \ --id id \ --call-control-id v3:MdI91X4lWFEs7IgbBEOT9M4AigoY08M0WWZFISt1Yw2axZ_IiE4pqg components: schemas: JoinConferenceRequest: required: - call_control_id type: object title: Join Conference Request properties: call_control_id: description: Unique identifier and token for controlling the call example: >- v2:T02llQxIyaRkhfRKxgAP8nY511EhFLizdvdUKJiSw8d6A9BborherQczRrZvZakpWxBlpw48KyZQ== type: string client_state: description: >- Use this field to add state to every subsequent webhook. It must be a valid Base-64 encoded string. Please note that the client_state will be updated for the participient call leg and the change will not affect conferencing webhooks unless the participient is the owner of the conference. example: aGF2ZSBhIG5pY2UgZGF5ID1d type: string command_id: description: >- Use this field to avoid execution of duplicate commands. Telnyx will ignore subsequent commands with the same `command_id` as one that has already been executed. example: 891510ac-f3e4-11e8-af5b-de00688a4901 type: string end_conference_on_exit: description: >- Whether the conference should end and all remaining participants be hung up after the participant leaves the conference. Defaults to "false". example: true type: boolean soft_end_conference_on_exit: description: >- Whether the conference should end after the participant leaves the conference. NOTE this doesn't hang up the other participants. Defaults to "false". example: true type: boolean hold: description: >- Whether the participant should be put on hold immediately after joining the conference. Defaults to "false". example: true type: boolean hold_audio_url: type: string example: http://example.com/message.wav description: >- The URL of a file to be played to the participant when they are put on hold after joining the conference. hold_media_name and hold_audio_url cannot be used together in one request. Takes effect only when "start_conference_on_create" is set to "false". This property takes effect only if "hold" is set to "true". hold_media_name: type: string example: my_media_uploaded_to_media_storage_api description: >- The media_name of a file to be played to the participant when they are put on hold after joining the conference. The media_name must point to a file previously uploaded to api.telnyx.com/v2/media by the same user/organization. The file must either be a WAV or MP3 file. Takes effect only when "start_conference_on_create" is set to "false". This property takes effect only if "hold" is set to "true". mute: description: >- Whether the participant should be muted immediately after joining the conference. Defaults to "false". example: true type: boolean start_conference_on_enter: description: >- Whether the conference should be started after the participant joins the conference. Defaults to "false". example: true type: boolean supervisor_role: description: >- Sets the joining participant as a supervisor for the conference. A conference can have multiple supervisors. "barge" means the supervisor enters the conference as a normal participant. This is the same as "none". "monitor" means the supervisor is muted but can hear all participants. "whisper" means that only the specified "whisper_call_control_ids" can hear the supervisor. Defaults to "none". example: whisper type: string enum: - barge - monitor - none - whisper whisper_call_control_ids: description: >- Array of unique call_control_ids the joining supervisor can whisper to. If none provided, the supervisor will join the conference as a monitoring participant only. example: - v2:Sg1xxxQ_U3ixxxyXT_VDNI3xxxazZdg6Vxxxs4-GNYxxxVaJPOhFMRQ - v2:qqpb0mmvd-ovhhBr0BUQQn0fld5jIboaaX3-De0DkqXHzbf8d75xkw type: array items: type: string beep_enabled: description: >- Whether a beep sound should be played when the participant joins and/or leaves the conference. Can be used to override the conference-level setting. enum: - always - never - on_enter - on_exit example: on_exit type: string region: $ref: '#/components/schemas/ConferenceRegion' example: call_control_id: v3:MdI91X4lWFEs7IgbBEOT9M4AigoY08M0WWZFISt1Yw2axZ_IiE4pqg client_state: aGF2ZSBhIG5pY2UgZGF5ID1d command_id: 891510ac-f3e4-11e8-af5b-de00688a4901 end_conference_on_exit: true hold: true hold_audio_url: http://www.example.com/audio.wav mute: true start_conference_on_enter: true supervisor_role: whisper whisper_call_control_ids: - v2:Sg1xxxQ_U3ixxxyXT_VDNI3xxxazZdg6Vxxxs4-GNYxxxVaJPOhFMRQ - v2:qqpb0mmvd-ovhhBr0BUQQn0fld5jIboaaX3-De0DkqXHzbf8d75xkw beep_enabled: always ConferenceRegion: description: >- Region where the conference data is located. Defaults to the region defined in user's data locality settings (Europe or US). example: US type: string enum: - Australia - Europe - Middle East - US ConferenceCommandResult: type: object title: Conference Command Result required: - result properties: result: type: string example: ok example: result: ok call-control_Errors: properties: errors: type: array items: $ref: '#/components/schemas/call-control_Error' call-control_Error: required: - code - title properties: code: type: string format: integer title: type: string detail: type: string source: type: object properties: pointer: description: JSON pointer (RFC6901) to the offending entity. type: string format: json-pointer parameter: description: Indicates which query parameter caused the error. type: string meta: type: object responses: ConferenceCommandResponse: description: Successful response upon making a conference command. content: application/json: schema: type: object title: Conference Command Response properties: data: $ref: '#/components/schemas/ConferenceCommandResult' UnauthorizedResponse: description: >- Unauthorized. Authentication failed - the required authentication headers were either invalid or not included in the request. content: application/json: schema: $ref: '#/components/schemas/call-control_Errors' example: errors: - code: '10009' title: Authentication failed detail: >- The required authentication headers were either invalid or not included in the request. meta: url: https://developers.telnyx.com/docs/overview/errors/10009 UnprocessableEntityResponse: description: >- Unprocessable entity. The request was well-formed but could not be processed due to semantic errors. This includes validation errors, invalid parameter values, call state errors, conference errors, queue errors, recording/transcription errors, and business logic violations. content: application/json: schema: $ref: '#/components/schemas/call-control_Errors' examples: missing_required_parameter: summary: Missing required parameter value: errors: - code: '10004' title: Missing required parameter detail: The 'to' parameter is required and cannot be blank. source: pointer: /to invalid_call_control_id: summary: Invalid call control ID value: errors: - code: '90015' title: Invalid Call Control ID detail: The call_control_id provided was not valid. source: pointer: /call_control_id call_already_ended: summary: Call has already ended value: errors: - code: '90018' title: Call has already ended detail: This call is no longer active and can't receive commands. call_not_answered: summary: Call not answered yet value: errors: - code: '90034' title: Call not answered yet detail: >- This call can't receive this command because it has not been answered yet. cannot_record_before_audio_started: summary: Cannot record before audio started value: errors: - code: '90020' title: Call recording triggered before audio started detail: >- Call recording cannot be started until audio has commenced on the call. transcription_already_active: summary: Transcription already active value: errors: - code: '90054' title: Call transcription is already in progress detail: Call transcription can not be started more than once. ai_assistant_already_active: summary: AI Assistant already active value: errors: - code: '90061' title: AI Assistant is already in progress detail: AI Assistant cannot be started more than once. conference_already_ended: summary: Conference has already ended value: errors: - code: '90019' title: Conference has already ended detail: >- This conference is no longer active and can't receive commands. conference_name_conflict: summary: Conference name conflict value: errors: - code: '90033' title: Unable to execute command detail: Conference with given name already exists and it's active. max_participants_reached: summary: Maximum participants reached value: errors: - code: '90032' title: Maximum number of participants reached detail: >- The maximum allowed value of `max_participants` has been reached at 100. queue_full: summary: Queue is full value: errors: - code: '90036' title: Queue full detail: The 'support' queue is full and can't accept more calls. call_already_in_queue: summary: Call already in queue value: errors: - code: '90038' title: Call already in queue detail: Call can't be added to a queue it's already in. invalid_connection_id: summary: Invalid connection ID value: errors: - code: '10015' title: Invalid value for connection_id (Call Control App ID) detail: >- The requested connection_id (Call Control App ID) is either invalid or does not exist. Only Call Control Apps with valid webhook URL are accepted. source: pointer: /connection_id invalid_phone_number_format: summary: Invalid phone number format value: errors: - code: '10016' title: Phone number must be in +E164 format detail: The 'to' parameter must be in E164 format. source: pointer: /to srtp_not_supported_for_pstn: summary: SRTP not supported for PSTN calls value: errors: - source: pointer: /media_encryption title: Media encryption not supported for PSTN calls detail: SRTP media encryption is not supported for PSTN calls. code: '10011' fork_not_found: summary: Call is not forked value: errors: - code: '90031' title: Call is not currently forked detail: >- Can't stop forking, because the call isn't currently forked. media_streaming_used: summary: Media streaming in use value: errors: - code: '90045' title: Media Streaming is used detail: This command can't be issued when media streaming is used. invalid_enumerated_value: summary: Invalid enumerated value value: errors: - code: '10032' title: Invalid enumerated value detail: 'The value must be one of: dual, single.' source: pointer: /record_channels value_outside_range: summary: Value outside of range value: errors: - code: '10033' title: Value outside of range detail: The value is outside of allowed range 1 to 5000 source: pointer: /max_participants securitySchemes: bearerAuth: scheme: bearer type: http ````