Grok Realtime

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Overview

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Configuration Requirements

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xAI API Key

• Field: grok_realtime_api_key
• Type: String (required)
• Purpose: Authenticates Coval’s connection to the Grok Voice Agent API
• Format: An xAI API key with Grok Voice Agent API access. Must start with xai-.
• Security: Stored encrypted and handled securely

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Agent System Instructions

• Field: grok_realtime_instructions
• Type: String (optional)
• Default: "" (model default instructions)
• Purpose: System prompt sent as the session instructions to the Grok voice model
• Use Cases: Role definition, behavior guidelines, response formatting
• Example: "You are a helpful customer support agent. Always be polite and provide accurate information."

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Model

• Field: grok_realtime_model
• Type: String (optional)
• Default: grok-voice-think-fast-1.0 (used when the field is omitted)
• Purpose: Selects which Grok voice model powers the agent

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Agent Voice

• Field: grok_realtime_voice
• Type: String (optional)
• Default: ara
• Purpose: Prebuilt voice used by the agent

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Simulation Timeout

• Field: simulation_timeout_seconds
• Type: Integer (optional)
• Default: 900 (15 minutes)
• Range: 1 to 1800 (30 minutes)
• Purpose: Maximum duration for a single simulated conversation

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Setup Instructions

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Creating via the API

curl -X POST https://api.coval.dev/v1/agents \
  -H "x-api-key: YOUR_COVAL_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "display_name": "Grok Realtime Voice Agent",
    "model_type": "MODEL_TYPE_GROK_REALTIME",
    "metadata": {
      "grok_realtime_api_key": "xai-...",
      "grok_realtime_instructions": "You are a helpful customer support agent...",
      "grok_realtime_model": "grok-voice-think-fast-1.0",
      "grok_realtime_voice": "ara",
      "simulation_timeout_seconds": 900
    }
  }'

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How Simulations Work

1. Opens a connection to the Grok Voice Agent API using your API key, model, voice, and system instructions
2. Plays the simulated user’s turns into the live session
3. Captures the agent’s audio responses and transcribes them
4. Records the full conversation transcript
5. Runs your configured metrics against the transcript

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Troubleshooting

• The key must start with xai- — the agent form flags keys without that prefix
• Confirm the key is valid in the xAI Console and has Grok Voice Agent API access

• Voice must be one of eve, ara, rex, sal, or leo. Other strings are rejected at save time.

• Grok Realtime has no temperature setting. Adjust the system instructions — for example, ask for concise, consistent answers, or give examples of the tone you want.

• Increase Simulation Timeout if conversations are being cut short
• Check that your system instructions don’t tell the agent to end calls immediately