# Configure evaluation judging

A judge checks a conversation's answers against the requirements in your suite. An application judge uses a check registered by your app. A Studio judge uses a model configured for Studio.

## Choose a judge

When launching a suite, select **Studio judge** or an available **App judge**. Studio saves that choice with the run. Missing judge configuration produces an error; it does not silently switch judges.

In Cloud, connect a supported provider in [Settings > Providers](/docs/cloud/evaluations#provider-credentials). Self-hosted operators configure the [Studio API's judge](/docs/self-hosting/configure-evaluations#studio-judge-configuration). Your application's workflow model remains configured in the app.

## Judge criteria and evidence

Write checks against the answer and evidence your app actually produces. If a check requires a successful product lookup, emit the relevant tool result with `toolExecution.emit: true`. The judge cannot verify a lookup from an unsupported claim in the answer alone.

Use `createEvals.defaults.evidence` for default evidence selection and `suite.evidence` for case-suite overrides. Keep credentials and private account tokens out of suites and evidence. See [the SDK evidence guide](/docs/sdk/guides/conversation-evals#compact-judge-evidence) for the supported fields.

> **Good to know:** Tool evidence and cost telemetry serve different purposes. `toolExecution.emit: true` supplies judge evidence; [normal telemetry](/docs/studio/connect-project) records the calls used for [workflow cost attribution](/docs/studio/evaluation-results#eval-run-costs).

## Read a verdict

Inspect each criterion's result and reason in the saved run. A completed workflow can fail a quality check. A judge request that fails, times out, or returns an invalid verdict is an evaluation error.

Next: [Read and compare results](/docs/studio/evaluation-results).