---
title: "Traces"
description: "Retrieve traces and annotate them with @arizeai/phoenix-client"
---

The traces module provides trace retrieval and trace-level annotation functions.

<section className="hidden" data-agent-context="relevant-source-files" aria-label="Relevant source files">
  <h2>Relevant Source Files</h2>
  <ul>
    <li>
      <code>src/traces/getTraces.ts</code> for the exact query shape and server
      requirement
    </li>
    <li>
      <code>src/traces/addTraceAnnotation.ts</code> for single annotation writes
    </li>
    <li>
      <code>src/traces/logTraceAnnotations.ts</code> for batched annotation writes
    </li>
    <li>
      <code>src/traces/types.ts</code> for the <code>TraceAnnotation</code> type
    </li>
  </ul>
</section>

## Retrieve Traces

Use `getTraces` when you want trace-centric pagination by project, optional inline spans, or filtering by session.

```ts
import { getTraces } from "@arizeai/phoenix-client/traces";

const result = await getTraces({
  project: { projectName: "support-bot" },
  startTime: new Date("2026-03-01T00:00:00Z"),
  endTime: new Date("2026-03-02T00:00:00Z"),
  includeSpans: true,
  limit: 50,
});

for (const trace of result.traces) {
  console.log(trace.trace_id);
}

console.log(result.nextCursor);
```

### Supported Filters

- `project`
- `startTime`
- `endTime`
- `sort`
- `order`
- `limit`
- `cursor`
- `includeSpans`
- `sessionId`

### Notes

- `getTraces` requires a Phoenix server that supports project trace listing
- Use the returned `nextCursor` to continue pagination
- Set `includeSpans` when you need a trace-centric fetch that also contains span details
- `project` accepts `{ project }`, `{ projectId }`, or `{ projectName }`

## Annotate a Single Trace

Use `addTraceAnnotation` to attach a label, score, or explanation to one trace. If you supply an `identifier`, Phoenix upserts the annotation when an annotation with that identifier already exists.

```ts
import { addTraceAnnotation } from "@arizeai/phoenix-client/traces";

const result = await addTraceAnnotation({
  traceAnnotation: {
    traceId: "abc123",
    name: "correctness",
    label: "correct",
    score: 1.0,
    annotatorKind: "HUMAN",
  },
});

// result is { id: string } when sync: true, or null when sync: false (default)
```

Set `sync: true` to receive the annotation ID immediately; omit it (or pass `false`) for higher-throughput async writes.

### TraceAnnotation Fields

| Field | Type | Required | Description |
|-------|------|----------|-------------|
| `traceId` | `string` | Yes | OpenTelemetry Trace ID (hex, no `0x` prefix) |
| `name` | `string` | Yes | What is being measured (e.g. `"groundedness"`). The name `"note"` is reserved — use `addTraceNote` instead. |
| `annotatorKind` | `"HUMAN" \| "LLM" \| "CODE"` | No | Defaults to `"HUMAN"` |
| `label` | `string` | At least one of label/score/explanation | Categorical result (e.g. `"correct"`) |
| `score` | `number` | At least one of label/score/explanation | Numeric result (e.g. `0.95`) |
| `explanation` | `string` | At least one of label/score/explanation | Free-text justification |
| `identifier` | `string` | No | Stable ID for idempotent upserts |
| `metadata` | `Record<string, unknown>` | No | Arbitrary context |

## Annotate Multiple Traces

Use `logTraceAnnotations` to batch-write annotations across many traces in a single request.

```ts
import { logTraceAnnotations } from "@arizeai/phoenix-client/traces";

const results = await logTraceAnnotations({
  traceAnnotations: [
    { traceId: "abc123", name: "faithfulness", score: 0.9, annotatorKind: "LLM" },
    { traceId: "def456", name: "faithfulness", score: 0.7, annotatorKind: "LLM" },
  ],
  sync: true,
});

for (const r of results) {
  console.log(r.id);
}
```

`logTraceAnnotations` sends all annotations in a single POST and returns an array of `{ id: string }` objects (or an empty array when `sync: false`).

<section className="hidden" data-agent-context="source-map" aria-label="Source map">
  <h2>Source Map</h2>
  <ul>
    <li><code>src/traces/getTraces.ts</code></li>
    <li><code>src/traces/addTraceAnnotation.ts</code></li>
    <li><code>src/traces/logTraceAnnotations.ts</code></li>
    <li><code>src/traces/types.ts</code></li>
    <li><code>src/types/projects.ts</code></li>
  </ul>
</section>