TypeScript

bryel is OpenTelemetry-native. On the server you have three ways in, all shipping the same OpenInference traces — models, tokens, cost, tool calls, full trajectory.

Vercel AI SDK

One processor + a per-call flag.

Any OTel app

Ship spans you already emit.

Provider SDKs

OpenAI / Anthropic / LangChain.

Vercel AI SDK

@bryel/vercel maps the AI SDK’s OpenTelemetry spans into OpenInference and ships them to bryel. You never wrap your model calls.

Install

bun add @bryel/vercel @vercel/otel

npm i @bryel/vercel @vercel/otel

pnpm add @bryel/vercel @vercel/otel

yarn add @bryel/vercel @vercel/otel

In instrumentation.ts — Next.js calls this on startup.

instrumentation.ts

import { registerOTel } from "@vercel/otel";
import { bryelVercelProcessor } from "@bryel/vercel";

export function register() {
  registerOTel({
    serviceName: "my-app",
    spanProcessors: [bryelVercelProcessor({ apiKey: process.env.BRYEL_KEY! })],
  });
}

Enable telemetry per call

const result = streamText({
  model: openai("gpt-5"),
  prompt,
  experimental_telemetry: {
    isEnabled: true,
    metadata: { sessionId, userId },
  },
});

A streamed span finalizes only once the stream is fully consumed — always drain it.

Any OpenTelemetry app

If your app already emits OpenInference spans, add bryelSpanProcessor to your provider — no mapping.

bun add @bryel/sdk-core @opentelemetry/sdk-trace-base

npm i @bryel/sdk-core @opentelemetry/sdk-trace-base

pnpm add @bryel/sdk-core @opentelemetry/sdk-trace-base

yarn add @bryel/sdk-core @opentelemetry/sdk-trace-base

import { NodeSDK } from "@opentelemetry/sdk-node";
import { bryelSpanProcessor } from "@bryel/sdk-core";

new NodeSDK({
  spanProcessors: [bryelSpanProcessor({ apiKey: process.env.BRYEL_KEY })],
}).start();

If your spans aren’t OpenInference yet, supply a SpanMapper (this is exactly what @bryel/vercel does):

import { buildSpanProcessor, type SpanMapper } from "@bryel/sdk-core";

const mapper: SpanMapper = {
  name: "my-framework",
  shouldMap: (span) => span.name.startsWith("my."),
  map: (span) => ({ /* OpenInference attributes to merge */ }),
};

const processor = buildSpanProcessor(mapper, { apiKey: process.env.BRYEL_KEY });

Provider SDKs

Calling OpenAI / Anthropic / LangChain directly? Add any OpenTelemetry instrumentation that emits GenAI spans, then ship them with bryelSpanProcessor — no call-site changes:

import { NodeSDK } from "@opentelemetry/sdk-node";
import { bryelSpanProcessor } from "@bryel/sdk-core";
// + the OpenTelemetry instrumentation for your provider SDK

new NodeSDK({
  instrumentations: [/* your GenAI instrumentation */],
  spanProcessors: [bryelSpanProcessor({ apiKey: process.env.BRYEL_KEY })],
}).start();

Grouping and feedback

The metadata you pass groups and joins your data:

string

Groups turns into one conversation.

string

The end user behind the run.

string

A per-turn id you mint (crypto.randomUUID()). bryel stamps it as bryel.interaction.id so feedback joins back to the turn.

API

string

required

Project API key (bk_…).

string

default:"https://ingest.eu.bryel.ai/v1/traces"

OTLP/HTTP endpoint. Override for self-hosting.

Record<string, string>

Extra headers, merged after auth.

bryelVercelProcessor (AI SDK, with mapping), bryelSpanProcessor (no mapping), and buildSpanProcessor(mapper, options) (custom mapping) all take these options and return an OTel SpanProcessor.

Getting started

SDK

Concepts

Guides

Vercel AI SDK

Any OTel app

Provider SDKs

Vercel AI SDK

Any OpenTelemetry app

Provider SDKs

Grouping and feedback

API

Vercel AI SDK

Any OTel app

Provider SDKs

​Vercel AI SDK

​Any OpenTelemetry app

​Provider SDKs

​Grouping and feedback

​API

Vercel AI SDK

Any OpenTelemetry app

Provider SDKs

Grouping and feedback

API