/openground), click Create New Playground to open the comparison runner at /openground/new.
Step 1: Prompt configuration
The first card has two tabs:- Custom - a free-text prompt box (placeholder: “Enter your prompt… Use
{{variable}}for dynamic values”). - Prompt Hub - a dropdown (placeholder: “Select a prompt from Prompt Hub”) to pick a saved prompt from Prompt Hub. Once selected, a version-tagged preview of the prompt’s content is shown.
{{variable}} placeholders, a Variables section automatically appears below with one input per variable, along with the note “These values will be substituted into your prompt before evaluation.”
Step 2: Select providers to compare
A grid of provider cards follows, each showing an avatar, name, model count, and a status badge - Configured or Configure.- Clicking a Configured card adds it to the comparison immediately, using its default model.
- Clicking an unconfigured card opens a setup dialog where you pick an API Key (from Vault) - with a shortcut to create one on the spot if your Vault is empty - and an optional default model, then click Save Configuration.
Step 3: Provider settings
Once you’ve selected at least one provider, a settings panel appears per provider:- Model - a dropdown of that provider’s supported models, each showing its context-window size and price per million tokens. You can also switch to Use Custom Model to type an arbitrary model ID directly, with its own input/output pricing.
- A Manage models shortcut opens model management - the same catalog as Costs → Manage models.
- Three sliders per provider:
- Temperature -
0to2 - Max Tokens -
100to4000 - Top P -
0to1
- Temperature -
There’s no field for a custom endpoint or base URL. You can point a provider at a custom model ID with your own pricing, but not at a self-hosted or custom API endpoint.

