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On this page
  • Default system prompt
  • Building your system prompt
  • Specifying a system prompt
Speech-to-Speech (EVI)Configuration

System Prompt

Define EVI’s behavior, responses, and style.

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A system prompt in the context of EVI is a set of instructions that guide the AI’s behavior, responses, and overall style during a chat session. It defines the specific goal or role for EVI, such as acting as a customer support representative, a fitness coach, or a travel advisor. This helps ensure the conversation stays aligned with your application’s intended focus.

Prompting Guide

See our tips and best practices on crafting effective system prompts to guide EVI’s response generation.

Default system prompt

If you do not specify a system prompt in your configuration, a default system prompt will be applied. You can find our default system prompt on GitHub for reference.

Building your system prompt

Prompts are managed as resources within our API and are version controlled. This enables you to:

  • Develop and refine system prompts over time.
  • Maintain consistent behavior across chat sessions.
  • Reuse and reference existing prompts in different configurations.
EVI Playground

Modify and test your system prompt directly in our EVI Playground

API Reference

See our API reference for how to manage Prompts through the API.

Specifying a system prompt

When creating an EVI config through the API, you have two options for specifying your system prompt:

  1. Reference an existing prompt: Specify the ID of a pre-existing, version-controlled Prompt. EVI will use the referenced prompt in the chat session.

    Specifying an existing prompt
    1curl -X POST https://api.hume.ai/v0/evi/configs \
    2 -H "X-Hume-Api-Key: <apiKey>" \
    3 -H "Content-Type: application/json" \
    4 -d '{
    5 "evi_version": "3",
    6 "name": "Sample Config",
    7 "prompt": {
    8 "id": "af699d45-2985-42cc-91b9-af9e5da3bac5",
    9 "version": 0
    10 }
    11 }'
  2. Define a new Prompt in the request: Provide the prompt text directly in your configuration request. In this case, a new prompt will be automatically created and associated with the configuration.

    Specifying an existing prompt
    1curl -X POST https://api.hume.ai/v0/evi/configs \
    2 -H "X-Hume-Api-Key: <apiKey>" \
    3 -H "Content-Type: application/json" \
    4 -d '{
    5 "evi_version": "3",
    6 "name": "Sample Config",
    7 "prompt": {
    8 "text": "Sample system prompt"
    9 }
    10 }'