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This tutorial creates a voice agent, integrating the realtime reasoning intelligence of Mercury 2 with Vapi. For this demo, you will need an Inception API key and a Vapi account.

Authentication

  1. Navigate to Integrations in the Vapi sidebar.
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  1. Under Model Providers, click into Custom LLM (bottom right).
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  1. Fill in your Inception API key and click Save.
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Setting up your Mercury voice agent

  1. Navigate to Agents in the Vapi sidebar and select Create Assistant.
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  1. Name your assistant and select your desired assistant template.
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  1. Select Custom llm from the Model dropdown:
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  1. Fill in model details as follows:
    • Set Custom LLM URL as https://api.inceptionlabs.ai/v1
    • Set Model as mercury-2
    • Set Temperature to 0.75
    • Set Max Tokens to a slightly higher value, like 4096. This is because the default reasoning effort is medium, and Max Tokens includes reasoning tokens.
    • Configure First Message Mode, First Message and System Prompt as desired.
      • Scroll down to manage Tools, Structured Outputs and more.
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  1. When you’re ready, hit Publish in the top right corner, and Talk to speak to Mercury 2!
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