Datadog Tagging Best Practices

Overview

This skill defines Datadog's official tagging best practices for unified service tagging across all telemetry (APM traces, logs, metrics).

The Three Core Tags (Required)

Datadog reserves three standard tags that automatically connect all telemetry:

Additional Recommended Tags

Tag Naming Rules

1. Lowercase only - Tags must be lowercase
2. Start with letter - Tags must begin with a letter
3. Alphanumeric + underscores - Use a-z, 0-9, _, -, :, /, .
4. Max 200 characters - Tag names limited to 200 chars
5. Colons for namespacing - Use : for hierarchical tags (e.g., team:backend)
6. No spaces - Use underscores or hyphens instead

Implementation Patterns

Python Scripts (ddtrace)

#!/usr/bin/env python3
from __future__ import annotations

import os

# Datadog Unified Service Tagging
try:
    from ddtrace import config, patch_all, tracer

    # Core tags (required)
    config.service = os.environ.get("DD_SERVICE", "script-name")
    config.env = os.environ.get("DD_ENV", "development")
    config.version = os.environ.get("DD_VERSION", "0.1.0")

    # Additional tags
    tracer.set_tags({
        "team": "platform",
        "component": "automation",
    })

    patch_all()
except ImportError:
    pass

Environment Variables (Shell/CI)

export DD_ENV=production
export DD_SERVICE=my-service
export DD_VERSION=1.2.3
export DD_TAGS="team:backend,component:api,cluster:tundra-dome"

Kubernetes Labels

metadata:
  labels:
    tags.datadoghq.com/env: "production"
    tags.datadoghq.com/service: "my-service"
    tags.datadoghq.com/version: "1.2.3"

Service Naming Conventions

Anti-Patterns to Avoid

• Over-tagging - Each tag adds cost; keep tag cardinality low
• High-cardinality values - Avoid UUIDs, timestamps, user IDs as tag values
• Inconsistent naming - Use same tag names across all services
• Missing core tags - Always set env, service, version
• Hardcoded values - Use environment variables for flexibility

Version Tag Strategies

Cost Optimization

• Limit custom tags to essential ones (team, component, cluster)
• Use tag inheritance from infrastructure where possible
• Avoid creating new tags for each deployment
• Use DD_TAGS for static tags shared across requests

References

• Unified Service Tagging
• Tagging Best Practices
• Assigning Tags