@mastra/laminar

Laminar observability exporter for Mastra applications.

Exports Mastra spans to Laminar via OTLP/HTTP (protobuf) and supports sending scorer results to Laminar Evaluators.

Installation

npm install @mastra/laminar

Usage

Zero-Config Setup

The exporter automatically reads credentials from environment variables:

# Required
LMNR_PROJECT_API_KEY=lmnr_...

# Optional
LMNR_BASE_URL=https://api.lmnr.ai
LAMINAR_ENDPOINT=https://api.lmnr.ai/v1/traces

import { LaminarExporter } from '@mastra/laminar';

const mastra = new Mastra({
  ...,
  observability: {
    configs: {
      laminar: {
        serviceName: 'my-service',
        exporters: [new LaminarExporter()],
      },
    },
  },
});

Explicit Configuration

import { LaminarExporter } from '@mastra/laminar';

const mastra = new Mastra({
  ...,
  observability: {
    configs: {
      laminar: {
        serviceName: 'my-service',
        exporters: [
          new LaminarExporter({
            apiKey: 'lmnr_...',
            baseUrl: 'https://api.lmnr.ai',
            endpoint: 'https://api.lmnr.ai/v1/traces', // Optional
            realtime: false, // Optional
          }),
        ],
      },
    },
  },
});

Configuration Options

| Option | Type | Description | | --------------- | ----------------------- | --------------------------------------------------------------------------------- | | apiKey | string | Laminar project API key. Defaults to LMNR_PROJECT_API_KEY env var | | baseUrl | string | Laminar base URL. Defaults to LMNR_BASE_URL env var or https://api.lmnr.ai | | endpoint | string | OTLP/HTTP traces endpoint. Defaults to LAMINAR_ENDPOINT env var or /v1/traces | | headers | Record<string,string> | Additional OTLP headers | | realtime | boolean | Flush after each span for immediate visibility. Defaults to false | | disableBatch | boolean | Disable batching (SimpleSpanProcessor). Defaults to false | | batchSize | number | Max spans per batch (BatchSpanProcessor). Defaults to 512 | | timeoutMillis | number | OTLP export timeout (ms). Defaults to 30000 |

Notes

• The exporter sets Laminar-specific attributes (lmnr.span.*, lmnr.association.properties.*) so traces render correctly in Laminar.