/**
 * Constants for MLflow Tracing
 */
/**
 * Enum for span types that can be used with MLflow Tracing
 */
export declare enum SpanType {
    LLM = "LLM",
    CHAIN = "CHAIN",
    AGENT = "AGENT",
    TOOL = "TOOL",
    CHAT_MODEL = "CHAT_MODEL",
    RETRIEVER = "RETRIEVER",
    PARSER = "PARSER",
    EMBEDDING = "EMBEDDING",
    RERANKER = "RERANKER",
    MEMORY = "MEMORY",
    UNKNOWN = "UNKNOWN"
}
/**
 * Constants for MLflow span attribute keys
 */
export declare const SpanAttributeKey: {
    EXPERIMENT_ID: string;
    TRACE_ID: string;
    INPUTS: string;
    OUTPUTS: string;
    SPAN_TYPE: string;
    TOKEN_USAGE: string;
    MESSAGE_FORMAT: string;
};
/**
 * Constants for MLflow trace metadata keys
 */
export declare const TraceMetadataKey: {
    SOURCE_RUN: string;
    MODEL_ID: string;
    SIZE_BYTES: string;
    SCHEMA_VERSION: string;
    TOKEN_USAGE: string;
    INPUTS: string;
    OUTPUTS: string;
};
/**
 * Constants for MLflow trace tag keys
 */
export declare const TraceTagKey: {
    MLFLOW_ARTIFACT_LOCATION: string;
};
/**
 * Current version of the MLflow trace schema
 */
export declare const TRACE_SCHEMA_VERSION = "3";
/**
 * The prefix for MLflow trace IDs
 */
export declare const TRACE_ID_PREFIX = "tr-";
/**
 * The default name for spans if the name is not provided when starting a span
 */
export declare const DEFAULT_SPAN_NAME = "span";
/**
 * Trace ID for no-op spans
 */
export declare const NO_OP_SPAN_TRACE_ID = "no-op-span-trace-id";
/**
 * Constants for token usage keys (matching Python TokenUsageKey)
 */
export declare const TokenUsageKey: {
    INPUT_TOKENS: string;
    OUTPUT_TOKENS: string;
    TOTAL_TOKENS: string;
};
/**
 * Max length of the request/response preview in the trace info.
 */
export declare const REQUEST_RESPONSE_PREVIEW_MAX_LENGTH = 1000;