> ## Documentation Index
> Fetch the complete documentation index at: https://arizeai-433a7140.mintlify.site/llms.txt
> Use this file to discover all available pages before exploring further.

# 04.13.2026 @arizeai/phoenix-otel 1.0

> Tracing helpers, decorators, context setters, and OpenInference semantic conventions ship from a single @arizeai/phoenix-otel import.

**Available in @arizeai/phoenix-otel 1.0.0+**

`@arizeai/phoenix-otel` now re-exports the full `@arizeai/openinference-core` and `@arizeai/openinference-semantic-conventions` surface so you can register tracing, wrap functions, decorate methods, set context attributes, and build rich OpenInference spans from a single import.

## Tracing Helpers

`withSpan`, `traceChain`, `traceAgent`, and `traceTool` wrap functions with OpenInference spans. Each helper records inputs, outputs, errors, and span kind, and resolves the default tracer when the wrapped function runs — so helpers defined at module scope follow global provider changes.

```typescript theme={null}
import {
  register,
  traceAgent,
  traceChain,
  traceTool,
  withSpan,
} from "@arizeai/phoenix-otel";

register({ projectName: "my-app" });

const searchDocs = traceTool(
  async (query: string) => fetch(`/api/search?q=${query}`).then((r) => r.json()),
  { name: "search-docs" }
);

const summarize = traceChain(
  async (text: string) => `Summary of ${text.length} chars`,
  { name: "summarize" }
);

const supportAgent = traceAgent(
  async (question: string) => {
    const docs = await searchDocs(question);
    return summarize(JSON.stringify(docs));
  },
  { name: "support-agent" }
);

const retrieveDocs = withSpan(
  async (query: string) => fetch(`/api/search?q=${query}`).then((r) => r.json()),
  { name: "retrieve-docs", kind: "RETRIEVER" }
);
```

## Decorators

The `observe` decorator wraps class methods with tracing while preserving `this`. Use TypeScript 5+ standard decorators.

```typescript theme={null}
import { OpenInferenceSpanKind, observe } from "@arizeai/phoenix-otel";

class ChatService {
  @observe({ kind: OpenInferenceSpanKind.CHAIN })
  async runWorkflow(message: string) {
    return `processed: ${message}`;
  }

  @observe({ name: "llm-call", kind: OpenInferenceSpanKind.LLM })
  async callModel(prompt: string) {
    return `model output for: ${prompt}`;
  }
}
```

## Context Attribute Setters

Propagate session IDs, user IDs, metadata, tags, and prompt templates to all child spans inside a context scope.

```typescript theme={null}
import {
  context,
  register,
  setMetadata,
  setSession,
  setUser,
  traceChain,
} from "@arizeai/phoenix-otel";

register({ projectName: "my-app" });

const handleQuery = traceChain(
  async (query: string) => `Handled: ${query}`,
  { name: "handle-query" }
);

await context.with(
  setMetadata(
    setUser(
      setSession(context.active(), { sessionId: "sess-123" }),
      { userId: "user-456" }
    ),
    { environment: "production" }
  ),
  () => handleQuery("Hello")
);
```

Available setters: `setSession`, `setUser`, `setMetadata`, `setTags`, `setAttributes`, `setPromptTemplate`. For manual spans, copy propagated attributes with `getAttributesFromContext(context.active())`.

## OpenInference Semantic Conventions

`@arizeai/openinference-semantic-conventions` is now re-exported directly from `@arizeai/phoenix-otel`. Import `SemanticConventions`, `OpenInferenceSpanKind`, and attribute name constants from one place instead of adding a second dependency.

```typescript theme={null}
import {
  OpenInferenceSpanKind,
  SemanticConventions,
} from "@arizeai/phoenix-otel";
```

## Attribute Builders

Build OpenInference-compatible span attributes directly for raw OpenTelemetry spans or custom processors.

```typescript theme={null}
import { getLLMAttributes, trace } from "@arizeai/phoenix-otel";

const tracer = trace.getTracer("llm-service");

tracer.startActiveSpan("llm-inference", (span) => {
  span.setAttributes(
    getLLMAttributes({
      provider: "openai",
      modelName: "gpt-4o-mini",
      inputMessages: [{ role: "user", content: "What is Phoenix?" }],
      outputMessages: [{ role: "assistant", content: "Phoenix is..." }],
      tokenCount: { prompt: 12, completion: 44, total: 56 },
      invocationParameters: { temperature: 0.2 },
    })
  );
  span.end();
});
```

Available builders: `getLLMAttributes`, `getEmbeddingAttributes`, `getRetrieverAttributes`, `getToolAttributes`, `getMetadataAttributes`, `getInputAttributes`, `getOutputAttributes`, `defaultProcessInput`, `defaultProcessOutput`.

## Redaction With OITracer

`OITracer` wraps an OpenTelemetry tracer and redacts or drops sensitive OpenInference attributes before spans are written. Configure via `traceConfig` or the `OPENINFERENCE_HIDE_*` environment variables.

```typescript theme={null}
import {
  OITracer,
  OpenInferenceSpanKind,
  trace,
  withSpan,
} from "@arizeai/phoenix-otel";

const tracer = new OITracer({
  tracer: trace.getTracer("my-service"),
  traceConfig: {
    hideInputs: true,
    hideOutputText: true,
    hideEmbeddingVectors: true,
    base64ImageMaxLength: 8_000,
  },
});

const safeLLMCall = withSpan(
  async (prompt: string) => `model response for ${prompt}`,
  { tracer, kind: OpenInferenceSpanKind.LLM, name: "safe-llm-call" }
);
```

<CardGroup cols={2}>
  <Card title="@arizeai/phoenix-otel Docs" icon="book" href="/docs/phoenix/sdk-api-reference/typescript/arizeai-phoenix-otel">
    Curated reference for register, tracing helpers, and context attributes.
  </Card>

  <Card title="Setup Tracing" icon="gear" href="/docs/phoenix/tracing/how-to-tracing/setup-tracing/setup-using-phoenix-otel">
    Install, register, and export traces from Node.js to Phoenix.
  </Card>
</CardGroup>