> ## Documentation Index
> Fetch the complete documentation index at: https://docs.voiceblox.ai/llms.txt
> Use this file to discover all available pages before exploring further.

# Troubleshooting

> Common issues and how to fix them.

# Troubleshooting

## The agent doesn't respond

**Check:**

* LLM API key is set in `.env.local`
* The LLM node is connected to the Framework node
* Restart the dev server after adding keys

## No voice output (silent agent)

**Check:**

* TTS API key is set
* TTS node is connected to the Framework node's `tts_in`
* Try a different TTS provider

## No voice input (agent can't hear me)

**Check:**

* Browser microphone permissions are granted
* STT API key is set
* STT node is connected to the Framework node's `stt_in`
* The builder STT key for the selected `BUILDER_STT_PROVIDER` is set (`BUILDER_STT_DEEPGRAM_API_KEY` for Deepgram, `BUILDER_STT_GEMINI_API_KEY` for Gemini)

## Session fails to start

**Check:**

* `LIVEKIT_URL`, `LIVEKIT_API_KEY`, `LIVEKIT_API_SECRET` are all set
* LiveKit credentials are valid (test in your LiveKit Cloud dashboard)
* No typos in the URL (must start with `wss://`)

## AI generator returns an error

**Check:**

* The builder LLM key for the selected `BUILDER_LLM_PROVIDER` is set (`BUILDER_LLM_ANTHROPIC_API_KEY` for Anthropic, `BUILDER_LLM_GEMINI_API_KEY` for Gemini)
* You have credits/quota with the selected provider
* The flow has the required nodes (framework, LLM, TTS, STT, start, end)

## Flow validation error

Voiceblox validates the graph before applying AI-generated operations. Common validation errors:

| Error                        | Fix                                                |
| ---------------------------- | -------------------------------------------------- |
| Missing framework node       | Add a LiveKit node                                 |
| No start node                | Add a Start node connected to the Framework        |
| If/Else directly after Start | Add a Burst or Open Talk between Start and If/Else |
| Categorize has no categories | Add at least two categories to the Categorize node |

## Step highlighting not working

**Check:**

* The LiveKit SDK is connected to the room
* Check browser console for WebSocket errors

## Restarting the agent

If the agent gets into a bad state, click **End Session** and then **Start Session** again to restart with a fresh session.