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    Interface EvaluationRule

    Live evaluation rule for incoming data.

    An evaluation rule answers:

    • which evaluator should be used
    • which target objects should trigger scoring
    • how often scoring should run
    • which target fields should populate each evaluator variable
    • whether the deployment is active, inactive, or paused

    Important status semantics:

    • enabled is the desired on/off setting from the client
    • status is the effective runtime state after Langfuse applies validation and blocking rules
    • enabled=true with status=paused means the rule should run, but Langfuse has paused it until the underlying problem is fixed
    {
     *         id: "erule_123",
     *         name: "answer-correctness-live",
     *         evaluator: {
     *             id: "evaltmpl_123",
     *             name: "answer-correctness",
     *             scope: LangfuseAPI.unstable.EvaluatorScope.Project,
     *             type: LangfuseAPI.unstable.EvaluatorType.LlmAsJudge
     *         },
     *         target: LangfuseAPI.unstable.EvaluationRuleTarget.Observation,
     *         enabled: true,
     *         status: LangfuseAPI.unstable.EvaluationRuleStatus.Active,
     *         pausedReason: null,
     *         pausedMessage: null,
     *         sampling: 1,
     *         filter: [{
     *                 type: "stringOptions",
     *                 column: "type",
     *                 operator: LangfuseAPI.unstable.EvaluationRuleOptionsFilterOperator.AnyOf,
     *                 value: ["GENERATION"]
     *             }],
     *         mapping: [{
     *                 variable: "input",
     *                 source: LangfuseAPI.unstable.EvaluationRuleMappingSource.Input
     *             }, {
     *                 variable: "output",
     *                 source: LangfuseAPI.unstable.EvaluationRuleMappingSource.Output
     *             }],
     *         createdAt: "2026-03-30T09:20:00.000Z",
     *         updatedAt: "2026-03-30T09:20:00.000Z"
     *     }
    interface EvaluationRule {
        createdAt: string;
        enabled: boolean;
        evaluator: unstable.EvaluationRuleEvaluator;
        filter: unstable.EvaluationRuleFilter[];
        id: string;
        mapping: unstable.EvaluationRuleMapping[];
        name: string;
        pausedMessage: null | string;
        pausedReason: null | string;
        sampling: number;
        status: unstable.EvaluationRuleStatus;
        target: unstable.EvaluationRuleTarget;
        updatedAt: string;
    }
    Index

    Properties

    createdAt enabled evaluator filter id mapping name pausedMessage pausedReason sampling status target updatedAt

    Properties

    createdAt: string

    Timestamp when the evaluation rule was created.

    enabled: boolean

    Desired enabled state configured by the client.

    evaluator: unstable.EvaluationRuleEvaluator

    Evaluator currently used by this rule.

    name and scope identify the evaluator family conceptually. id is the currently active evaluator version in that family. If you create a newer project version with the same evaluator name later, existing evaluation rules are moved to it automatically.

    filter: unstable.EvaluationRuleFilter[]

    List of filter conditions used to decide whether a target should be evaluated.

    id: string

    Stable evaluation rule identifier.

    mapping: unstable.EvaluationRuleMapping[]

    Variable mappings used to populate evaluator runtime variables from the live target object.

    name: string

    Human-readable deployment name. This is independent from the evaluator name.

    pausedMessage: null | string

    Human-readable explanation when status=paused, otherwise null.

    pausedReason: null | string

    Machine-readable reason when status=paused, otherwise null.

    sampling: number

    Fraction of matching target objects that should be evaluated.

    Must be greater than 0 and less than or equal to 1.

    • 1 means evaluate every matching target.
    • 0.25 means evaluate approximately 25% of matching targets.
    status: unstable.EvaluationRuleStatus

    Effective runtime status after Langfuse applies validation and blocking rules.

    target: unstable.EvaluationRuleTarget

    Target object type that should trigger scoring.

    updatedAt: string

    Timestamp when the evaluation rule was last updated.

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