Robovoice TCP STT Protocol

Overview

Robovoice acts as a client: it connects to a remote STT server over TCP, sends control messages when the user presses/releases the PTT key, and receives transcript messages back. The STT server captures audio from a microphone, runs speech recognition (Moonshine), and sends transcripts back over the same connection.

[Robovoice client] --TCP--> [STT server :5210]
     │                            │
     ├── {"event":"on"}\n  ──────►│
     │                            ├── capture audio
     ├── {"event":"off"}\n ──────►│
     │                            ├── run STT
     │◄── {"final":true,...}\n ──┤

Transport

Protocol: TCP (reliable, ordered, connection-oriented)
Server endpoint: configurable in Robovoice UI (default 127.0.0.1:5210)
Framing: newline-delimited JSON (NDJSON) — each message is a single UTF-8 JSON object terminated by \n
Auto-reconnect: if the connection drops, Robovoice retries every 3 seconds until the server is available

Control messages (client → server)

Sent by Robovoice when the user presses/releases the PTT key.

{"event": "on"}

{"event": "off"}

Field	Type	Description
`event`	string	`"on"` (PTT pressed) or `"off"` (PTT released)

Transcript messages (server → client)

Sent by the server back to Robovoice over the same TCP connection.

{"final": false, "text": "hello world"}

{"final": true, "text": "hello world how are you"}

Field	Type	Required	Description
`final`	bool	yes	`true` = final result, `false` = partial
`text`	string	yes	The transcript text (may be empty for partials)

Semantics

final: false — intermediate recognition result (partial). Robovoice logs these but does not act on them (only final triggers TTS).
final: true — complete utterance. Robovoice feeds this to the TTS engine and speaks it.

Malformed JSON or unknown field values are silently dropped by the client.

2.3 KiB Raw Blame History