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Documentation Index

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Check disconnection reasons via the Call History tab in the dashboard or the Get Call API.
Phone numbers that make many short calls in a short period may be marked as spam at the carrier level, causing calls to show up as dial_failed.

Disconnection Reasons

Expected / Normal

ReasonCall StatusDescription
user_hangupendedUser hung up
agent_hangupendedAgent hung up
call_transferendedAgent transferred the call
voicemail_reachedendedVoicemail detected and agent is configured to handle it
ivr_reachedendedIVR detected and agent is configured to hang up
inactivityendedCall ended due to end_call_after_silence_ms threshold
max_duration_reachedendedCall ended due to maximum duration setting

Not Connected

ReasonDescription
dial_busyOutbound call — number dialed is busy
dial_failedOutbound call — dialing failed with no or unknown SIP error code
dial_no_answerOutbound call — number didn’t answer
invalid_destinationNumber is invalid, has spaces/invalid characters, or wrong format (check E.164)
telephony_provider_permission_deniedSIP trunk credentials not authenticated
telephony_provider_unavailableTelephony provider is down
sip_routing_errorSIP routing has too many hops or is in a loop
marked_as_spamNumber marked as spam. See Spam Likely Overview.
user_declinedUser declined the outbound call

Errors

ReasonDescription
concurrency_limit_reachedConcurrency limit hit — add retry with exponential backoff, or upgrade plan
no_valid_paymentNo valid payment on file, or service shut down due to overdue bill
scam_detectedScam detected for that particular agent
error_llm_websocket_openLLM websocket failed to open — check Custom LLM URL and server reachability
error_llm_websocket_lost_connectionLLM websocket dropped during the call
error_llm_websocket_runtimeLLM websocket received a non-1000 closing signal from your server
error_llm_websocket_corrupt_payloadLLM websocket received unspecified payload
error_no_audio_receivedNo audio received from telephony or web frontend after connection
error_asrASR encountered a problem
error_retellUnspecified UponAI-side problem
error_unknownUnknown error
error_user_not_joinedUser didn’t join web call within 30s of startWebCall
registered_call_timeoutPhone call placed 5+ minutes after registration