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.
Browser-local preparation and checks · no model calls · no input storage
Your output
result.jsonComplete 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.