# API Tracing > Instrument API requests with spans and distributed tracing. Use when tracking request latency or debugging API issues. Use when this capability is needed. - Skill: `tomevault-io/api-tracing` (Agent Skill, multi-file: 2 files) - Install (CLI): `npx skillmds@latest add tomevault-io/api-tracing` - Raw SKILL.md: https://api.skillmd.com/api/skills/tomevault-io/api-tracing/raw - Safety review: pending - Works with: Claude Code, Claude.ai, OpenAI Codex - Category: Integrations & APIs - Author: tomevault-io (https://skillmd.com/u/tomevault-io) - Updated: 2026-09-17 - Page: https://skillmd.com/skills/tomevault-io/api-tracing --- # API Tracing Measure API requests and correlate with backend traces. ## What to Capture (OTel-Compatible) | Attribute | OTel Name | Purpose | |-----------|-----------|---------| | Method | `http.request.method` | GET, POST, etc. | | Status | `http.response.status_code` | Success/failure | | URL | `url.path` | Endpoint (sanitized) | | Duration | `http.request.duration` | Request time (ms) | Using OTel naming now = easier migration later. ## Key Thresholds | Metric | Good | Acceptable | Poor | |--------|------|------------|------| | p50 | <200ms | <500ms | >500ms | | p95 | <1s | <2s | >2s | | Error rate | <0.1% | <1% | >1% | ## What NOT to Log | Don't | Why | |-------|-----| | Request bodies | PII risk | | Auth headers | Security | | Full response data | Size limits | | User tokens | Security | **Do log:** Request ID, sanitized path, status code, duration, error type. ## Implementation See `templates/api-interceptor.ts` for fetch/axios interceptors. Use Read tool to load template when generating implementation. ## Related - `skills/error-tracking` - API error handling - `skills/route-transition-tracking` - Data fetch during navigation - `references/otel-web.md` - OpenTelemetry naming --- > Converted and distributed by [TomeVault](https://tomevault.io/claim/nexus-labs-automation) — claim your Tome and manage your conversions.