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POST
/
calls
/
{call_control_id}
/
actions
/
transfer
JavaScript
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.calls.actions.transfer('call_control_id', {
  to: '+18005550100 or sip:username@sip.telnyx.com;secure=srtp',
});

console.log(response.data);
{ "data": { "result": "ok" } }

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.

Authorizations

​
Authorization
string
header
required

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

Path Parameters

​
call_control_id
string
required

Unique identifier and token for controlling the call

Body

application/json

Transfer call request

​
to
string
required

The DID or SIP URI to dial out to. For SIP URI destinations, append ;secure=true or ;secure=srtp to enable SRTP media encryption for that endpoint, or ;secure=dtls to enable DTLS media encryption for that endpoint. If media_encryption is set to SRTP or DTLS, it takes precedence over any per-endpoint secure URI parameter. You may also append a comma followed by DTMF digits (e.g. +18004247767,200) to play those digits as DTMF once the transfer destination answers — equivalent to setting send_digits_on_answer separately. If both are present, the explicit send_digits_on_answer parameter takes precedence.

Example:

"+18005550100 or sip:username@sip.telnyx.com;secure=srtp"

​
from
string

The from number to be used as the caller id presented to the destination (to number). The number should be in +E164 format. This attribute will default to the to number of the original call if omitted.

Example:

"+18005550101"

​
from_display_name
string

The from_display_name string to be used as the caller id name (SIP From Display Name) presented to the destination (to number). The string should have a maximum of 128 characters, containing only letters, numbers, spaces, and -_~!.+ special characters. If ommited, the display name will be the same as the number in the from field.

Example:

"Company Name"

​
privacy
enum<string>

Indicates the privacy level to be used for the call. When set to id, caller ID information (name and number) will be hidden from the called party. When set to none or omitted, caller ID will be shown normally.

Available options:
id,
none
Example:

"id"

​
audio_url
string

The URL of a file to be played back when the transfer destination answers before bridging the call. The URL can point to either a WAV or MP3 file. media_name and audio_url cannot be used together in one request.

Example:

"http://example.com/message.wav"

​
send_digits_on_answer
string

DTMF digits to send automatically after the transfer destination answers. Useful for reaching an extension behind an IVR (e.g. "200" to dial extension 200 once the called party picks up). Allowed characters: 0-9, A-D, w (0.5s pause), W (1s pause), *, #. Maximum 64 characters. When omitted, no automatic DTMF is sent. May also be supplied inline by appending ,<digits> to to (e.g. to=+18004247767,200); if both forms are present, this explicit field takes precedence.

Example:

"wwww200"

​
early_media
boolean
default:true

If set to false, early media will not be passed to the originating leg.

Example:

false

​
media_name
string

The media_name of a file to be played back when the transfer destination answers before bridging the call. 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.

Example:

"my_media_uploaded_to_media_storage_api"

​
timeout_secs
integer<int32>
default:30

The number of seconds that Telnyx will wait for the call to be answered by the destination to which it is being transferred. If the timeout is reached before an answer is received, the call will hangup and a call.hangup webhook with a hangup_cause of timeout will be sent. Minimum value is 5 seconds. Maximum value is 600 seconds.

Example:

60

​
time_limit_secs
integer<int32>
default:14400

Sets the maximum duration of a Call Control Leg in seconds. If the time limit is reached, the call will hangup and a call.hangup webhook with a hangup_cause of time_limit will be sent. For example, by setting a time limit of 120 seconds, a Call Leg will be automatically terminated two minutes after being answered. The default time limit is 14400 seconds or 4 hours and this is also the maximum allowed call length.

Required range: 30 <= x <= 14400
Example:

600

​
park_after_unbridge
string

Specifies behavior after the bridge ends (i.e. the opposite leg either hangs up or is transferred). If supplied with the value self, the current leg will be parked after unbridge. If not set, the default behavior is to hang up the leg.

Example:

"self"

​
answering_machine_detection
enum<string>
default:disabled

Enables Answering Machine Detection. When a call is answered, Telnyx runs real-time detection to determine if it was picked up by a human or a machine and sends an call.machine.detection.ended webhook with the analysis result. If 'greeting_end' or 'detect_words' is used and a 'machine' is detected, you will receive another 'call.machine.greeting.ended' webhook when the answering machine greeting ends with a beep or silence. If detect_beep is used, you will only receive 'call.machine.greeting.ended' if a beep is detected.

Available options:
premium,
detect,
detect_beep,
detect_words,
greeting_end,
disabled
​
answering_machine_detection_config
object

Optional configuration parameters to modify 'answering_machine_detection' performance. Only total_analysis_time_millis and greeting_duration_millis parameters are applicable when premium is selected as answering_machine_detection.

​
custom_headers
Custom SIP Header · object[]

Custom headers to be added to the SIP INVITE.

Example:
[
  { "name": "head_1", "value": "val_1" },
  { "name": "head_2", "value": "val_2" }
]
​
client_state
string

Use this field to add state to every subsequent webhook. It must be a valid Base-64 encoded string.

Example:

"aGF2ZSBhIG5pY2UgZGF5ID1d"

​
target_leg_client_state
string

Use this field to add state to every subsequent webhook for the new leg. It must be a valid Base-64 encoded string.

Example:

"aGF2ZSBhIG5pY2UgZGF5ID1d"

​
command_id
string

Use this field to avoid duplicate commands. Telnyx will ignore any command with the same command_id for the same call_control_id.

Example:

"891510ac-f3e4-11e8-af5b-de00688a4901"

​
media_encryption
enum<string>
default:disabled

Defines whether media should be encrypted on the new call leg. For SIP URI destinations, media encryption can also be requested per endpoint with the secure URI parameter: ;secure=true or ;secure=srtp enables SRTP, and ;secure=dtls enables DTLS. This parameter, when set to SRTP or DTLS, takes precedence over the per-endpoint secure value.

Available options:
disabled,
SRTP,
DTLS
​
sip_auth_username
string

SIP Authentication username used for SIP challenges.

Example:

"username"

​
sip_auth_password
string

SIP Authentication password used for SIP challenges.

Example:

"password"

​
sip_headers
SIP Header · object[]

SIP headers to be added to the SIP INVITE. Currently only User-to-User header is supported.

Example:
[
  { "name": "User-to-User", "value": "value" }
]
​
sip_transport_protocol
enum<string>
default:UDP

Defines SIP transport protocol to be used on the call.

Available options:
UDP,
TCP,
TLS
​
sound_modifications
Sound modifications · object

Use this field to modify sound effects, for example adjust the pitch.

Example:
{
  "pitch": 0.8,
  "semitone": -2,
  "octaves": 0.1,
  "track": "both"
}
​
webhook_url
string

Use this field to override the URL for which Telnyx will send subsequent webhooks to for this call.

Example:

"https://www.example.com/server-b/"

​
webhook_url_method
enum<string>
default:POST

HTTP request type used for webhook_url.

Available options:
POST,
GET
Example:

"GET"

​
mute_dtmf
enum<string>
default:none

When enabled, DTMF tones are not passed to the call participant. The webhooks containing the DTMF information will be sent.

Available options:
none,
both,
self,
opposite
Example:

"opposite"

​
record
enum<string>

Start recording automatically after an event. Disabled by default.

Available options:
record-from-answer
Example:

"record-from-answer"

​
record_channels
enum<string>
default:dual

Defines which channel should be recorded ('single' or 'dual') when record is specified.

Available options:
single,
dual
Example:

"single"

​
record_format
enum<string>
default:mp3

Defines the format of the recording ('wav' or 'mp3') when record is specified.

Available options:
wav,
mp3
Example:

"wav"

​
record_max_length
integer<int32>
default:0

Defines the maximum length for the recording in seconds when record is specified. The minimum value is 0. The maximum value is 43200. The default value is 0 (infinite).

Example:

1000

​
record_timeout_secs
integer<int32>
default:0

The number of seconds that Telnyx will wait for the recording to be stopped if silence is detected when record is specified. The timer only starts when the speech is detected. Please note that call transcription is used to detect silence and the related charge will be applied. The minimum value is 0. The default value is 0 (infinite).

Example:

100

​
record_track
enum<string>
default:both

The audio track to be recorded. Can be either both, inbound or outbound. If only single track is specified (inbound, outbound), channels configuration is ignored and it will be recorded as mono (single channel).

Available options:
both,
inbound,
outbound
Example:

"outbound"

​
record_trim
enum<string>

When set to trim-silence, silence will be removed from the beginning and end of the recording.

Available options:
trim-silence
Example:

"trim-silence"

​
record_custom_file_name
string

The custom recording file name to be used instead of the default call_leg_id. Telnyx will still add a Unix timestamp suffix.

Required string length: 1 - 40
Example:

"my_recording_file_name"

​
sip_region
enum<string>
default:US

Defines the SIP region to be used for the call.

Available options:
US,
Europe,
Canada,
Australia,
Middle East
Example:

"Canada"

​
preferred_codecs
string

The list of comma-separated codecs in order of preference to be used during the call. The codecs supported are G722, PCMU, PCMA, G729, OPUS, VP8, H264, AMR-WB.

Example:

"G722,PCMU,PCMA,G729,OPUS,VP8,H264"

​
webhook_urls
object

A map of event types to webhook URLs. When an event of the specified type occurs, the webhook URL associated with that event type will be called instead of webhook_url. Events not mapped here will use the default webhook_url.

Example:
{
  "call.answered": "https://www.example.com/webhooks/answered",
  "call.hangup": "https://www.example.com/webhooks/hangup"
}
​
webhook_urls_method
enum<string>
default:POST

HTTP request method to invoke webhook_urls.

Available options:
POST,
GET
Example:

"POST"

​
webhook_retries_policies
object

A map of event types to retry policies. Each retry policy contains an array of retries_ms specifying the delays between retry attempts in milliseconds. Maximum 5 retries, total delay cannot exceed 60 seconds.

Example:
{
  "call.answered": { "retries_ms": [1000, 2000, 5000] }
}

Response

Successful response upon making a call control command.

​
data
Call Control Command Result · object
Example:
{ "result": "ok" }