Choosing a Model (Anthropic Claude)

Compatibility

Verified against Testronaut CLI v1.10.0. Run testronaut config to inspect the effective configuration used by your installed version.

Testronaut supports Anthropic Claude models for agentic browser workflows, including native tool calls and screenshots.

Setup

Create or manage a key in the Claude Platform console, and follow Anthropic's official getting-started guide. Testronaut reads the key from ANTHROPIC_API_KEY.

Select Anthropic Claude during initialization:

testronaut --init

Add your API key to .env:

ANTHROPIC_API_KEY=sk-ant-...

The generated configuration uses the canonical provider ID anthropic:

{
  "provider": "anthropic",
  "model": "claude-sonnet-5"
}

Model	Best for
`claude-sonnet-5`	Recommended balance of capability, latency, and cost
`claude-opus-5`	Most demanding workflows and deeper reasoning
`claude-haiku-4-5`	Fast, cost-conscious smoke tests and larger suites

Model access and rate limits depend on your Anthropic account. Testronaut forwards the selected model ID directly to the Anthropic Messages API.

testronaut --provider=anthropic --model=claude-opus-5

--provider=claude is accepted as a convenience alias. Environment overrides work too:

TESTRONAUT_PROVIDER=anthropic TESTRONAUT_MODEL=claude-haiku-4-5 testronaut

The selected provider and model are included in local and uploaded reports.