Quality Gates

A quality gate checks the model's answer before it goes back to you. A gate has four options:

• Approve the answer — the run continues.
• Reject with a retry — the runtime sends the reason back to the model and tries again.
• Replace the answer — the gate returns its own result instead.
• Reject without a retry — the run fails.

Implementing a Gate

This example checks that the answer is valid JSON:

public sealed class JsonSchemaGate : IAgentQualityGate
{
    public string Name => "JsonSchema";
    public int Priority => 100;
    public bool AppliesTo(IAgentContext context) => true;

    public Task<QualityGateResult> EvaluateAsync(
        AgentResult result,
        IAgentContext context,
        CancellationToken ct)
    {
        var valid = IsValidJson(result.Output);
        return Task.FromResult(new QualityGateResult(
            Approved: valid,
            Retry: !valid,
            Reason: valid ? null : "Output must be valid JSON."));
    }
}

services.AddAgentQualityGate<JsonSchemaGate>();

The gate returns a QualityGateResult with three core fields: Approved (is the answer acceptable?), Retry (should the model try again?), and Reason (the explanation for the model).

Retry Behavior

When a gate sets Retry = true, the runtime sends the gate's Reason to the model with the next attempt. This tells the model what to fix. The number of retries is limited by the max_quality_retries request parameter or by the DefaultMaxQualityRetries runtime option.

A gate can also return a ReplacementResult. Then its own output replaces the model's answer, and there is no retry.

Scoping

Gates support agent-scoped registration. For example, a URL structure gate can run only for runs of the UrlResearchAgent.