eval-search-rubric (Search Rubric)

You can run this example with:

npx promptfoo@latest init --example eval-search-rubric
cd eval-search-rubric

This example demonstrates how to use the search-rubric assertion type to verify that LLM outputs contain accurate, current information.

Overview

The search-rubric assertion allows you to verify facts by searching the web in real-time. This is particularly useful for:

• Current events and news
• Stock prices and financial data
• Weather information
• Recent company information
• Any time-sensitive data

Running the Example

npx promptfoo eval

How It Works

1. The LLM generates a response to your prompt
2. The search-rubric assertion extracts the claim you want to verify
3. A provider with web search capabilities searches for current information
4. The assertion passes or fails based on whether the output matches current web data

Provider Support

Anthropic Claude

• Web search capabilities via tool configuration (launched in 2025)
• Requires explicit web_search_20250305 tool configuration
• Pricing: $10 per 1,000 searches plus standard token costs

OpenAI

• Requires web_search_preview tool configuration
• Works with gpt-5.1, o4-mini, and other Responses API models

Perplexity

• Built-in web search capabilities
• No additional configuration needed

Configuration

assert:
  - type: search-rubric
    value: 'search query to verify'
    threshold: 0.8 # Optional: minimum accuracy score (0-1)

Notes

• Search rubric assertions add latency (2-5 seconds per assertion)
• Use caching during development: npx promptfoo eval --cache
• Be specific with your search queries for better results