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Interface: NormalizedDtmfReceived

Defined in: packages/agentos/src/io/channels/telephony/types.ts:368

DTMF (Dual-Tone Multi-Frequency) digit received during a call.

DTMF events do NOT trigger a call state transition -- the call remains in its current state (typically listening or active). They are relayed as informational events so higher-level logic (e.g., IVR menus, PIN entry) can react to caller key-presses.

Provider behavior differences​

  • Twilio: DTMF arrives both via <Gather> webhook callbacks (as Digits param) and via the media stream WebSocket (as dtmf events with duration).
  • Telnyx: DTMF arrives only via call.dtmf.received HTTP webhooks -- never over the media stream WebSocket.
  • Plivo: DTMF arrives via <GetDigits> XML callback (as Digits param) in webhook POST bodies.

Example​

if (event.kind === 'call-dtmf') {
  console.log(`User pressed ${event.digit} for ${event.durationMs}ms`);
}

Extends​

  • NormalizedEventBase

Properties​

digit​

digit: string

Defined in: packages/agentos/src/io/channels/telephony/types.ts:376

The digit pressed by the caller.

Standard DTMF digits: '0'-'9', '*', '#'. Extended DTMF (rarely supported): 'A'-'D'.

durationMs?​

optional durationMs: number

Defined in: packages/agentos/src/io/channels/telephony/types.ts:383

How long the key was pressed in milliseconds, when available.

Not all providers report duration -- Twilio's media stream includes it, but Telnyx and Plivo webhook payloads typically omit it.

eventId​

eventId: string

Defined in: packages/agentos/src/io/channels/telephony/types.ts:266

Provider-assigned event ID for idempotency.

Inherited from​

NormalizedEventBase.eventId

kind​

kind: "call-dtmf"

Defined in: packages/agentos/src/io/channels/telephony/types.ts:369

providerCallId​

providerCallId: string

Defined in: packages/agentos/src/io/channels/telephony/types.ts:268

Provider-assigned call ID.

Inherited from​

NormalizedEventBase.providerCallId

timestamp​

timestamp: number

Defined in: packages/agentos/src/io/channels/telephony/types.ts:270

Unix timestamp (ms).

Inherited from​

NormalizedEventBase.timestamp