Axiom AI SDK provides flexible redaction policies to control what data is captured in OpenTelemetry spans. This allows you to balance observability needs with privacy and compliance requirements.

Built-in redaction policies

Axiom AI SDK provides two built-in redaction policies:
PolicyWhat gets capturedWhat gets excludedWhen to use
AxiomDefaultFull dataFull observability
OpenTelemetryDefaultModel metadata, token usage, error infoPrompt text, AI responses, tool args and resultsPrivacy-first
If you don’t specify a redaction policy, Axiom AI SDK applies AxiomDefault. To determine which redaction policy fits your needs, see the following comparison:

AxiomDefault policy

By default, Axiom AI SDK captures all data for maximum observability.What gets captured:
  • Full prompt text and AI responses in chat spans
  • Complete tool arguments and return values on tool spans
  • All standard OpenTelemetry attributes (model name, token usage, etc.)
Capturing full message content increases span size and storage costs.
When to use:
  • You need full visibility into AI interactions
  • Data privacy isn’t a concern
  • Debugging complex AI workflows

What gets captured

To determine which redaction policy fits your needs, see the following examples about what gets captured with each defaultpolicy:
{
  "gen_ai.operation.name": "chat",
  "gen_ai.request.model": "gpt-4o-mini",
  "gen_ai.input.messages": "[{\"role\":\"user\",\"content\":[{\"type\":\"text\",\"text\":\"Hello, how are you?\"}]}]",
  "gen_ai.output.messages": "[{\"role\":\"assistant\",\"content\":\"I'm doing well, thank you for asking!\"}]",
  "gen_ai.usage.input_tokens": 12,
  "gen_ai.usage.output_tokens": 15,
  "gen_ai.usage.total_tokens": 27
}

Global configuration

Set a default redaction policy for your entire application using initAxiomAI:
import { trace } from '@opentelemetry/api';
import { initAxiomAI, RedactionPolicy } from 'axiom/ai';

const tracer = trace.getTracer("my-tracer");

initAxiomAI({ tracer, redactionPolicy: RedactionPolicy.AxiomDefault });
In Quickstart, initAxiomAI is called in your instrumentation file (/src/instrumentation.ts).

Per-operation override

You can configure different policies for each operation. Axiom resolves redaction policies in the following order (from highest to lowest precedence):
  1. Per-operation policy
  2. Global policy
  3. Default policy
Override the global or default policy for specific operations by passing a redactionPolicy to withSpan:
import { withSpan, RedactionPolicy } from 'axiom/ai';
import { generateText } from 'ai';

const result = await withSpan(
  { capability: 'customer_support', step: 'handle_sensitive_query' },
  async (span) => {
    span.setAttribute('user.id', userId);
    return generateText({
      model: wrappedModel,
      prompt: 'Process this sensitive customer data...'
    });
  },
  { redactionPolicy: RedactionPolicy.OpenTelemetryDefault }
);

Custom redaction policies

Create custom policies by defining an AxiomAIRedactionPolicy object:
import { trace } from '@opentelemetry/api';
import { initAxiomAI, AxiomAIRedactionPolicy } from 'axiom/ai';

const tracer = trace.getTracer("my-tracer");

// Custom policy: capture messages but not tool payloads
const customPolicy: AxiomAIRedactionPolicy = {
  captureMessageContent: 'full',
  mirrorToolPayloadOnToolSpan: false
};

initAxiomAI({ tracer, redactionPolicy: customPolicy });
The AxiomAIRedactionPolicy object has two properties:
captureMessageContent
'full' | 'off'
default:"'full'"
Controls whether prompt and response text is included in chat spans.
  • 'full': Include complete message content
  • 'off': Exclude all message content
mirrorToolPayloadOnToolSpan
boolean
default:"true"
Controls whether tool arguments and results are duplicated on tool spans.
  • true: Mirror tool data for easier querying
  • false: Only capture tool metadata (name, description)
The built-in policies configure the AxiomAIRedactionPolicy object in the following way:
Default policycaptureMessageContentmirrorToolPayloadOnToolSpan
AxiomDefault'full'true
OpenTelemetryDefault'off'false