List Calls (Deprecated)

Authentication header containing API key (find it in dashboard). The format is "Bearer YOUR_API_KEY"

The calls will be sorted by start_timestamp, whether to return the calls in ascending or descending order.

Limit the number of calls returned.

The pagination key to continue fetching the next page of calls. Pagination key is represented by a call id here, and it's exclusive (not included in the fetched calls). The last call id from the list calls is usually used as pagination key here. If not set, will start from the beginning.

Unique id of the call. Used to identify in LLM websocket and used to authenticate in audio websocket.

Corresponding agent id of this call.

Where the audio websocket would connect from would determine the format / protocol of websocket messages, and would determine how our server read audio bytes and send audio bytes.:

• web: The protocol defined by Retell, commonly used for connecting from web frontend. Also useful for those who want to manipulate audio bytes directly.

• twilio: The websocket protocol defined by Twilio, used when your system uses Twilio, and supplies Retell audio websocket url to Twilio.

The audio encoding of the call. The following formats are supported:

• s16le 16 bit linear PCM audio, the native format for web audio capture and playback.

• mulaw non-linear audio encoding technique used in telephony. Commonly used by Twilio.

Sample rate of the conversation, the input and output audio bytes will all conform to this rate. Check the audio source, audio format, and voice used for the agent to select one that works. supports value ranging from [8000, 48000]. Note for Twilio mulaw encoding, the sample rate has to be 8000.

• s16le sample rate recommendation (natively supported, lowest latency):

  • elevenlabs voices: 16000, 22050, 24000, 44100.

  • openai voices: 24000.

  • deepgram voices: 8000, 16000, 24000, 32000, 48000.

Status of call.

• registered: Call id issued, ready to make a call using this id.

• ongoing: Call connected and ongoing.

• ended: The underlying websocket has ended for the call. Either user or agent hanged up, or call transferred.

• error: Call encountered error.

If users stay silent for a period after agent speech, end the call. The minimum value allowed is 10,000 ms (10 s). This value, if set, would overwrite the agent level end_call_after_silence_ms parameter.

The caller number.

The callee number.

Direction of the phone call. Not populated for web call.

An arbitrary object for storage purpose only. You can put anything here like your internal customer id associated with the call. Not used for processing. You can later get this field from the call object.

Add optional dynamic variables in key value pairs of string that injects into your Retell LLM prompt and tool description. Only applicable for Retell LLM.

If set, will drop the call if machine (voicemail, IVR) is detected. If not set, default value of false will apply.

Whether this call opts out of sensitive data storage like transcript, recording, logging.

Begin timestamp (milliseconds since epoch) of the call. Available after call starts.

End timestamp (milliseconds since epoch) of the call. Available after call ends.

Transcription of the call. Available after call ends.

Transcript of the call in the format of a list of utterance, with timestamp. Available after call ends.

Transcript of the call weaved with tool call invocation and results. It precisely captures when (at what utterance, which word) the tool was invoked and what was the result. Available after call ends.

Recording of the call. Available after call ends.

Public log of the call, containing details about all the requests and responses received in LLM WebSocket, latency tracking for each turntaking, helpful for debugging and tracing. Available after call ends.

End to end latency (from user stops talking to agent start talking) tracking of the call, available after call ends. This latency does not account for the network trip time from Retell server to user frontend. The latency is tracked every time turn change between user and agent.

LLM latency (from issue of LLM call to first token received) tracking of the call, available after call ends. When using custom LLM. this latency includes LLM websocket roundtrip time between user server and Retell server.

LLM websocket roundtrip latency (between user server and Retell server) tracking of the call, available after call ends. Only populated for calls using custom LLM.

The reason for the disconnection of the call. Read details desciption about reasons listed here at Disconnection Reason Doc.

• BETA feature, schema might change, might not always be populated. Please do not rely on this object schema for post processing. Post conversation evaluation of the call. Including information such as sentiment, intent, call completion status and other metrics. Available after call ends. Subscribe to call_analyzed webhook event type to receive it once ready.