Agora Conversational AI — Filler Words Recipe (Python)

  

The filler words recipe in the Agora Conversational AI recipes family. A friendly voice agent that plays natural filler phrases during LLM latency gaps and says a graceful goodbye when the conversation ends. Fully zero-key — OpenAI is Agora-managed (no OPENAI_API_KEY required unless you bring your own account).

Pipeline: DeepgramSTT(nova-3) → OpenAI (friendly assistant) → MiniMaxTTS

Prerequisites

• Python 3.10+
• Bun
• Agora CLI — makes generating an App ID + App Certificate easy

Run It

# 1. Install web deps + create the Python venv
bun run setup

# 2. Add Agora credentials (CLI), or edit server/.env.local by hand
agora login
agora project use <your-project>          # select which project to use
agora project env write server/.env.local # writes App ID + Certificate

# 3. Run backend + web
bun run dev

Open http://localhost:3000 → Start Conversation → ask anything and listen for filler phrases between your question and the agent's answer.

Working from a clone

If you cloned this repo (rather than scaffolding via the Agora CLI), the steps above are complete as written: bun run setup creates the Python venv and installs web dependencies, then bun run dev brings up both services. You still need Agora credentials in server/.env.local before a conversation can connect.

Services:

• Frontend — http://localhost:3000
• Backend — http://localhost:8000
• Mock LLM — N/A (managed OpenAI, no local service)
• API docs — http://localhost:8000/docs

Deploy

Deploy web (Next.js) and server (a reachable FastAPI backend). Set AGENT_BACKEND_URL in the web deployment so the Next rewrites reach the backend.

A backend-only Docker image is published to ghcr.io/AgoraIO-Conversational-AI/recipe-agent-filler-words on v* tags. It exposes BACKEND-ONLY (:8000). No separate LLM container is needed — OpenAI is Agora-managed.

Environment variables

Backend env file: `server/.env.example`.

Commands

bun run setup            # install web deps + create server/ venv
bun run dev              # run backend (:8000) + web (:3000)

bun run doctor           # prerequisite check (no creds needed)
bun run doctor:local     # + .env.local + credentials checks

bun run verify           # web-only gate (no Agora creds needed)
bun run verify:local     # full local gate: backend compile + smoke tests + web build
bun run clean            # remove venvs and build artifacts

Tests run standalone (no Agora cloud needed): pytest in server/, plus bun run verify in web/. CI runs them on Linux/macOS/Windows × Python 3.10 & 3.13.

Architecture

Browser (localhost:3000)
  │  fetch /api/*
  ▼
Next.js  ──rewrite──▶  Agent backend  (server/, localhost:8000)
                          │  starts agent session (managed OpenAI vendor)
                          │  filler_words: static phrases during LLM latency
                          │  farewell_config: graceful exit on stop
                          ▼
                       Agora ConvoAI Cloud
                          │  Deepgram STT (managed, nova-3)
                          │  OpenAI assistant (Agora-managed, keyless)
                          │  MiniMax TTS (managed)
                          ▼
                       User hears the agent (with filler phrases during latency)

No separate llm/ service — OpenAI is Agora-managed and requires no API key. See ARCHITECTURE.md.

What You Get

• A Next.js web client (:3000) that drives the RTC/RTM lifecycle and only ever calls /api/*.
• A FastAPI agent backend (:8000) that owns Agora token generation and the agent session lifecycle.
• The /api/get_config · /api/startAgent · /api/stopAgent contract between the web client and the backend (Next rewrites, no Route Handlers).
• Managed keyless OpenAI powering the assistant — Agora-managed, no OPENAI_API_KEY required.
• filler_words static phrase list played during LLM latency (SDK 2.0.0 supports mode: "static" only).
• farewell_config graceful exit: the agent speaks a farewell before leaving the channel.
• Zero-key setup — the full pipeline runs with no LLM API key by default.

How It Works

1. The browser calls /api/get_config, which Next rewrites to the backend; the

backend mints an Agora token from AGORA_APP_ID + AGORA_APP_CERTIFICATE.

1. The browser joins the RTC channel, then calls /api/startAgent; the backend

starts an agent session using the managed OpenAI vendor with filler_words and farewell_config configured.

1. The user speaks. Agora runs STT (Deepgram, nova-3) and produces a transcript.
2. While the LLM is generating a response, Agora plays a randomly selected

filler phrase from the static list, masking the silence.

1. The LLM response arrives and is spoken via MiniMax TTS.
2. /api/stopAgent ends the session. The agent speaks a farewell

(farewell_config) before leaving the channel.

Repo Map

• web/ — Next.js frontend (:3000); RTC/RTM lifecycle and UI.
• server/ — FastAPI agent backend (:8000); Agora tokens + agent lifecycle, managed OpenAI assistant.
• ARCHITECTURE.md — system shape and component boundaries.
• AGENTS.md — guide for coding agents working in this repo.

Troubleshooting

More Docs

• ARCHITECTURE.md
• AGENTS.md

License

Released under the MIT License.