CLI
Evalution ships a single command that starts the local playground.
Usage
npx evalution [ui [path]]evalution— start the playground for the current directory.evalution ui— same as above;uiis currently the only named subcommand.evalution ui <path>— start for<path>instead of the current directory.
How a project is found
From the starting directory (the current directory, or <path> if given),
Evalution walks up the directory tree looking for a .evalution/config.ts
file. The first directory that contains one becomes the project root, and its
config is loaded.
If no .evalution/config.ts is found anywhere up the tree, Evalution starts in
onboarding mode and guides you through creating one. See Configuration for the config file format.
On startup Evalution opens the playground in your default browser automatically.
Environment
| Variable | Effect |
|---|---|
PORT | Port for the local server. When set, it’s used as-is. When unset, Evalution uses 3000, falling back to the next free port if it’s already taken. |
EVALUTION_NO_OPEN | When set to any value, Evalution does not open the playground in your browser on start — useful for CI and remote or headless hosts. |
Provider API keys
To run prompts in the playground, set the applicable API key environment variable for each AI provider you use, for example:
OPENAI_API_KEYANTHROPIC_API_KEYGOOGLE_GENERATIVE_AI_API_KEY
If an .env file is found in the project root, it is loaded automatically before the server starts. This is the recommended place to keep these keys. Do not commit it to version control.