Disconnection reasons

Every value of disconnection_reason, what sets it in Tried, and the call_status it leads to.

disconnection_reason on the call object says why a call ended. The values are defined by DISCONNECTION_REASONS in packages/shared (42 values). The field is null while a call is registered or ongoing.

You can filter on it in Call history, in analytics charts, in QA cohorts and with filter_criteria.disconnection_reason on list-calls. Analytics charts and dashboards break calls down by it.

How it maps to call_status#

A call that never started ends as not_connected when its reason is one of the connection failures marked not_connected below. Every other ending is ended. A call that could not be placed at all (the media room could not be prepared) is stored with call_status: error and dial_failed.

Post-call analysis treats dial_busy, dial_failed, dial_no_answer, invalid_destination, concurrency_limit_reached, voicemail_reached, and any reason starting with error, as unsuccessful in mock mode, and sets in_voicemail to true only for voicemail_reached. See Post-call analysis.

Normal endings#

Value	Set when
`user_hangup`	The caller left the room or hung up. Also used when the API closes a call whose runtime stopped reporting, if the call was ongoing or inbound.
`agent_hangup`	The agent ended the call (an end call tool or end node).
`call_transfer`	The agent transferred the call to another number, or an inbound call over the concurrency limit was transferred to the number's fallback number.
`voicemail_reached`	Voicemail detection found an answering machine and the agent's voicemail action ran.
`ivr_reached`	IVR detection found a phone menu and the agent has an `ivr_option`, so it hung up.
`inactivity`	Nobody spoke for longer than the silence policy allows after the reminders were used.
`max_duration_reached`	The call hit the agent's `max_call_duration_ms`.
`manual_stopped`	You ended the call with `POST /v2/stop-call/:call_id` or End Call in Live Monitoring.
`user_requested_dnc`	DNC detection is on (`enable_dnc_detection`), the caller asked not to be called and confirmed. The linked contact is marked Do not call.
`scam_detected`	The guardrails flagged the caller as a scam. The agent says the guardrail fallback message and hangs up.
`guardrail_triggered`	Guardrails blocked 3 turns (input or output) in one call.
`call_take_over`	A dashboard user took over the call in Live Monitoring. The value is kept when the call later ends for another reason.

Transfer agent endings#

These are set on calls handled by a transfer agent (is_transfer_agent) during an agentic warm transfer.

Value	Set when
`transfer_bridged`	The transfer agent connected the caller to the transferee (the bridge transfer tool, or the transferee's voicemail with a `bridge_transfer` voicemail action).
`transfer_cancelled`	The transfer agent cancelled the transfer (the cancel transfer tool).

Connection failures#

All of these lead to call_status: not_connected when the call never started.

Value	Set when
`dial_busy`	SIP 486 or 600 on an outbound dial, or a busy error from the carrier.
`dial_no_answer`	SIP 408, 480 or 487, or a dial timeout. Also used when the API closes an outbound call that never reported back.
`user_declined`	SIP 603.
`marked_as_spam`	SIP 608. The phone number is also flagged as spam in Phone Numbers.
`invalid_destination`	SIP 400, 404, 410, 484, 485 or 604, or a not-found error.
`telephony_provider_permission_denied`	SIP 401, 403 or 407.
`telephony_provider_unavailable`	SIP 502, 503 or 504.
`dial_failed`	Any other dial failure, or the call could not be placed.
`sip_routing_error`	No outbound trunk for the number, or `register-phone-call` SIP routing is not configured.
`registered_call_timeout`	A `register-phone-call` call was not dialled within 5 minutes.
`error_user_not_joined`	A web call's browser never joined the room.
`concurrency_limit_reached`	No concurrency slot was free: an inbound caller waited in the queue and the fallback transfer did not happen, or a registered call could not be admitted.
`no_concurrency_fallback`	No slot was free for an inbound call and the number has no fallback number.
`no_valid_payment`	A batch call could not be dialled because the workspace has no credit. The attempt is kept as a call so it shows in the batch results.

A failed outbound dial also stores the carrier error text in metadata.dial_error.

Errors#

Value	Set when
`error_llm`	The LLM (or a speech-to-speech model) failed and the call could not continue.
`error_asr`	Speech to text failed.
`error_tts`	Text to speech failed.
`error_unknown`	Any other runtime failure, or the API closed a call with no better reason.
`error_llm_websocket_open`	A custom LLM agent could not open its WebSocket, or has no `llm_websocket_url`.
`error_llm_websocket_lost_connection`	The custom LLM WebSocket closed and reconnects were used up.
`error_llm_websocket_runtime`	The custom LLM WebSocket raised an error during the call.
`error_llm_websocket_corrupt_payload`	The custom LLM server sent a frame Tried could not parse.

See Custom LLM for the WebSocket protocol.

Defined but not set on calls#

These values are in the enum so payloads stay compatible, but Tried does not currently write them to a call:

Value	Note
`credit_exhausted`, `budget_reached`	When credit is used up or the monthly budget is reached, the API refuses the request with HTTP 402 and `error_code` set to one of these values. No call record is created.
`user_requested_callback`	Not emitted.
`error_no_audio_received`	Not emitted.
`network_blocked`	Not emitted.
`error_retell`	Not emitted.

Gotchas#

The first reason recorded is kept. If the agent hangs up and the caller's hang-up arrives a moment later, the call stays agent_hangup.
In the text simulator, a call the agent does not end itself ends with user_hangup, or max_duration_reached when it hits the simulation limit.
Alerting's Transfer call failures metric counts calls that called a transfer tool but did not end with call_transfer. See Alerting.