BraintrustExporter

Sends AI tracing data to Braintrust for eval and observability.

Constructor

new BraintrustExporter(config: BraintrustExporterConfig)

BraintrustExporterConfig

interface BraintrustExporterConfig {
  apiKey?: string;
  endpoint?: string;
  projectName?: string;
  logLevel?: "debug" | "info" | "warn" | "error";
  tuningParameters?: Record<string, any>;
}

Methods

exportEvent

async exportEvent(event: AITracingEvent): Promise<void>

Exports a tracing event to Braintrust.

export

async export(spans: ReadOnlyAISpan[]): Promise<void>

Batch exports spans to Braintrust.

shutdown

async shutdown(): Promise<void>

Flushes pending data and shuts down the client.

Usage

import { BraintrustExporter } from "@mastra/braintrust";

const exporter = new BraintrustExporter({
  apiKey: process.env.BRAINTRUST_API_KEY,
  projectName: "my-ai-project",
});

Span Type Mapping

AI Span Type	Braintrust Type
LLM_GENERATION	llm
LLM_CHUNK	llm
TOOL_CALL	tool
MCP_TOOL_CALL	tool
WORKFLOW_CONDITIONAL_EVAL	function
WORKFLOW_WAIT_EVENT	function
All others	task