# Analyze Trace > Walk a Lensflare trace span-by-span and explain timing, errors, and parent/child structure. Use when the user pastes a trace id, asks "why is this slow", or wants a request-level post-mortem of a real production / dev request captured in Lensflare. Use when this capability is needed. - Skill: `tomevault-io/analyze-trace` (Agent Skill, multi-file: 2 files) - Install (CLI): `npx skillmds@latest add tomevault-io/analyze-trace` - Raw SKILL.md: https://api.skillmd.com/api/skills/tomevault-io/analyze-trace/raw - Safety review: pending (external: skill-scanner PASS, skillspector PASS) - Works with: Claude Code, Claude.ai, OpenAI Codex - Category: Coding & Dev Tools - Author: tomevault-io (https://skillmd.com/u/tomevault-io) - Updated: 2026-09-17 - Page: https://skillmd.com/skills/tomevault-io/analyze-trace --- # Analyze a trace in Lensflare 1. If the user supplied a `traceId`, use it. Otherwise call `lensflare:queryTelemetry` to find a relevant trace (filter by `serviceName`, time, or attributes). Pick the trace whose root span has the highest `durationUs` or whose `status = "error"`. 2. Call `lensflare:getTrace` with the resolved `datasetId` and `traceId`. If it returns `null`, double-check the `traceId` with `queryTelemetry` (`traceId = ""`) before reporting back. 3. Read `summary.spanCount` and `summary.erroredSpanCount`. If errors exist, lead with them: name + service + `durationUs`. 4. Walk `spans` in order. Highlight the longest span, the deepest chain, and any span whose `status = "error"` or whose duration is more than 50% of its parent's. 5. Surface `relatedEvents` only when they materially explain a failure (e.g. an exception event on the failing span). 6. End with a one-line root-cause hypothesis and a suggested follow-up query. Example: _"to see all requests with this error: `attributes.http.status_code = 500 and serviceName = \"api\"`"_. --- > Source: [voidhashcom/lensflare](https://github.com/voidhashcom/lensflare) — distributed by [TomeVault](https://tomevault.io).