Free · no signup · browser-local

Promptfoo YAML Config Builder for Prompts and Assertions

Prepare multiple literal prompts, explicit provider IDs, variables and deterministic assertions as promptfooconfig.yaml. Download the config without executing model calls.

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Browser-local preparation and checks · no model calls · no input storage

Configure the check

Each test uses vars and assert. Assertions: equals, contains, not-contains, is-json. No executable providers, file references or arbitrary code. Running the downloaded configuration can incur model charges.

Your output

result.json

Complete the input to preview and export your result.

These are local preparation and validation tools. A passing check is limited to the stated rules; services are not called, authenticated or executed.

Getting started

Add literal prompt variants, list supported provider IDs and supply test cases, then download promptfooconfig.yaml.

Before you use the result

The config is generated without executing it. Running Promptfoo separately needs model access and may incur charges; executable providers and file references are excluded.

Try an example

Load the built-in example, change one value and inspect the actual exported result.

How it works

Bounded browser-local parsing and deterministic rules; no model calls, arbitrary code or remote schema fetches.

Frequently asked questions

Prepare a literal YAML config with prompts, provider IDs, variables and deterministic assertions.

How do I use Promptfoo Evaluation Config Builder?

Add literal prompt variants, list supported provider IDs and supply test cases, then download promptfooconfig.yaml.

Does this tool upload my data?

Inputs and files are processed in your browser. Page-view analytics do not contain your tool input.

What should I check before using the result?

The config is generated without executing it. Running Promptfoo separately needs model access and may incur charges; executable providers and file references are excluded.