# Choose an Agent and Model

URL: https://docs.testvibe.com/ai-generation/choose-agent-and-model

Generation settings live in **Settings → AI Model** . They control how much reasoning effort the generation agent spends per generation and how long a single generation is allowed to run.

AI runs on TestVibe's metered first-party service — usage is billed in credits and you do not need to provide a provider API key.

## The Settings

| Setting | What it controls | Model | The AI model TestVibe uses for feature drafting and Playwright code generation. TestVibe currently offers a single first-party model, so there is nothing to pick — the field simply names it. | Reasoning effort | Low, Medium, or High. Higher effort produces more thorough tests but uses more credits and takes longer. | Generation timeout (minutes) | The maximum time one generation may run before TestVibe stops it and marks the feature failed rather than shipping an unfinished test. Empty uses the 60-minute default; values are clamped to 5–120 minutes. 

New projects default to **Medium** reasoning effort and the 60-minute generation timeout.

Tests generate with the **TestVibe Assistant** — reasoning effort maps to the underlying provider's effort setting. Self-hosted installs configured with a custom OpenAI-compatible endpoint see their own model list here instead; see [AI models (self-hosted)](/self-hosting/ai-models) if that applies to your install.

A generated test only reaches **generated** status after TestVibe replays the whole assembled spec end-to-end and it passes — this validation always runs and cannot be turned off.

## When To Keep Defaults

Keep the defaults when:

- you are doing the quickstart
- your team already configured the project
- generation is producing acceptable output
- you want consistent results across the team

## When To Change

| Situation | Try | Output quality is weak on complex flows | Raise reasoning effort to High. | Generation feels slow or uses too many credits for routine tests | Lower the reasoning effort. | A heavy feature is hitting the generation timeout | Raise **Generation timeout (minutes)** , up to 120. Most features finish well under the 60-minute default. 

## After Changing

Run a small generation first. Compare the output against the same expectations:

- Does it follow the Gherkin?
- Does it use the correct UI?
- Does it include real assertions?
- Does it generate code your team can review?
If the new settings work well, save them as the project default.

## Related Help

- [How AI generation works](/ai-generation/how-ai-generation-works)
- [Regenerate a test](/ai-generation/regenerate-test)
- [Credit Usage](/account-settings/credit-usage)