deepgram-rust-conversational-stt

# Using Deepgram Conversational STT (Rust SDK) Use this skill for Deepgram Flux, the crate's supported turn-based conversational streaming path. ## When to use this product - Building turn-based STT for voice-agent pipelines. - Handling `TurnEvent::{StartOfTurn, EndOfTurn, EagerEndOfTurn, TurnResumed, Update}`. - Tuning end-of-turn behavior with `eot_threshold`, `eager_eot_threshold`, and `eot_timeout_ms`. ## Authentication Flux is under the `listen` feature. ```toml [dependencies] deepgram = { version = "0.10.0", default-features = false, features = ["listen"] } tokio = { version = "1", features = ["full"] } futures = "0.3" ``` ```rust let dg = deepgram::Deepgram::new(std::env::var("DEEPGRAM_API_KEY")?)?; ``` ## Quick start ```rust use std::{io::Write, time::Duration}; use deepgram::{ common::{ flux_response::{FluxResponse, TurnEvent}, options::{Encoding, Model, Options}, }, Deepgram, }; use futures::stream::StreamExt; static PATH_TO_FILE: &str = "examples/audio/sample-mono.wav"; static AUDIO_CHUNK_SIZE: usize = 18_063; static FRAME_DELAY: Duration = Duration::from_millis(100); #[tokio::main] async fn main() -> Result<(), Box<dyn std::error::Error>> { let api_key = std::env::var("DEEPGRAM_API_KEY")?; let dg = Deepgram::new(&api_key)?; let options = Options::builder() .model(Model::FluxGeneralEn) .eot_threshold(0.75) .eot_timeout_ms(5000) .keyterms(["activate", "cancel"]) .build(); let mut results = dg .transcription() .flux_request_with_options(options) .encoding(Encoding::Linear32) .sample_rate(44100) .file(PATH_TO_FILE, AUDIO_CHUNK_SIZE, FRAME_DELAY) .await?; println!("Flux Request ID: {}", results.request_id()); while let Some(result) = results.next().await { match result? { FluxResponse::Connected { request_id, sequence_id } => { println!("Connected: {request_id} (seq: {sequence_id})"); } FluxResponse::TurnInfo { event, turn_index, transcript, end_of_turn_confidence, .. } => { match event { TurnEvent::StartOfTurn => println!("▶ [Turn {turn_index}] START"), TurnEvent::EndOfTurn => println!("✓ [Turn {turn_index}] END ({end_of_turn_confidence:.2}): {transcript}"), TurnEvent::Update => { if !transcript.is_empty() { print!("\r[Turn {turn_index}] UPDATE: {transcript}"); std::io::stdout().flush().unwrap(); } } _ => {} } } FluxResponse::FatalError { code, description, .. } => { eprintln!("{code}: {description}"); break; } FluxResponse::Unknown(value) => println!("unknown: {value}"), } } Ok(()) } ``` ## Key parameters - Entrypoints: `flux_request()`, `flux_request_with_options(options)`. - Flux transport builder fields: `encoding`, `sample_rate`, then `.file(...)`, `.stream(...)`, or `.handle().await?`. - Flux-specific tuning in shared `OptionsBuilder`: `model(Model::FluxGeneralEn)`, `eot_threshold`, `eager_eot_threshold`, `eot_timeout_ms`, `keyterms`. - Main response type: `common::flux_response::FluxResponse`. ## API reference (layered) 1. **In-repo** - `src/listen/flux.rs` - `src/common/flux_response.rs` - `src/common/options.rs` - `examples/transcription/flux/simple_flux.rs` - `tests/flux_unknown_messages.rs` - `tests/flux_e2e.rs` 2. **OpenAPI** - Raw spec: `https://developers.deepgram.com/openapi.yaml` - Endpoint reference: `https://developers.deepgram.com/reference/speech-to-text/listen-flux` 3. **AsyncAPI** - Raw spec: `https://developers.deepgram.com/asyncapi.yaml` - Flux channel docs are surfaced from the same product reference page above 4. **Context7** - `/llmstxt/developers_deepgram_llms_txt` 5. **Product docs** - `https://developers.deepgram.com/docs/stt/getting-started` ## Gotchas 1. **Flux is English-only in this crate's model surface.** The default supported model is `Model::FluxGeneralEn`. 2. **Real-time pacing matters even more than standard streaming.** The example warns that bad chunk size / delay values can break turn detection. 3. **Unknown events are intentional.** `FluxResponse::Unknown` and `TurnEvent::Unknown` are there for forward compatibility; handle them instead of assuming exhaustiveness. 4. **Use Flux for turn-taking, not full agent control.** If you need TTS replies, prompts, or tool calls, that is Voice Agent territory and not a typed Rust SDK surface yet. ## Example files in this repo - `examples/transcription/flux/simple_flux.rs` - `examples/transcription/flux/simple_flux_token.rs` - `examples/transcription/flux/microphone_flux.rs` - `tests/flux_unknown_messages.rs` - `tests/flux_e2e.rs` ## Central product skills For cross-language Deepgram product knowledge — the consolidated API reference, documentation finder, focused runnable recipes, third-party integration examples, and MCP setup — install the central skills: ```bash npx skills add deepgram/skills ``` This SDK ships language-idiomatic code skills; `deepgram/skills` ships cross-language product knowledge (see `api`, `docs`, `recipes`, `examples`, `starters`, `setup-mcp`).