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observability-and-instrumentation
80 / 100 · Low risk
Fine to try.
By addyosmani/agent-skills (GitHub) · coding · 117,315 stars · scanned at commit 39b723c
Instruments code so production behavior is visible and diagnosable. Use when adding logging, metrics, tracing, or alerting. Use when shipping any feature that runs in production and you need evidence it works. Use when production issues are reported but you can't tell what happened from the available data.
Works with any agent that supports SKILL.md skills.
What this skill can do
Connects to the internet
The author does not mention this. It runs automatically when the plugin is installed.
Found in 16 places.
Show 13 more
- hooks/SDD-CACHE.md, line 57
The stored body is not raw HTML — `WebFetch` post-processes each response through a model using the caller's prompt, so what we cache is one agent's reading of - hooks/SDD-CACHE.md, line 65
| `PreToolUse WebFetch` | If an entry exists, sends a `HEAD` request with `If-None-Match` / `If-Modified-Since`. On `304`, blocks the fetch and returns the cach - hooks/SDD-CACHE.md, line 66
| `PostToolUse WebFetch` | Captures the response, issues a `HEAD` request to record the current `ETag` / `Last-Modified`, and stores `{url, prompt, etag, last_m - hooks/SDD-CACHE.md, line 76
- Cache hit: `WebFetch` is blocked via exit code 2. Claude Code delivers the hook's stderr payload back to the agent as a tool error — this is the intended sign - hooks/SDD-CACHE.md, line 77
- Cache miss or stale: `WebFetch` runs normally; the result is stored for next time. - hooks/SDD-CACHE.md, line 121
6. Verify the second `WebFetch` is blocked and the cached content is returned (visible in the session transcript as a tool error with `[sdd-cache]` prefix). - hooks/SDD-CACHE.md, line 157
- **Every cache write costs an extra HEAD.** Claude Code doesn't expose the response headers that `WebFetch` already received, so the post hook re-queries the o - hooks/sdd-cache-post.sh, line 82
HEAD_OUT=$(curl -sI -L --max-time 5 "$URL" 2>/dev/null | tr -d '\r' || true) - hooks/sdd-cache-pre.sh, line 71
STATUS=$(curl -sI -o /dev/null -w "%{http_code}" \ - hooks/sdd-cache-pre.sh, line 78
dbg "not 304, letting WebFetch proceed" - hooks/sdd-cache-pre.sh, line 85
dbg "cache HIT, blocking WebFetch with ${#CONTENT} bytes of cached content" - hooks/sdd-cache-pre.sh, line 97
printf 'content below as if WebFetch had just returned it.\n\n' - hooks/sdd-cache-pre.sh, line 99
printf 'Original WebFetch prompt: "%s". If your angle differs, judge\n' "$ORIGINAL_PROMPT"
Downloads and installs other software
The author does not mention this. It runs automatically when the plugin is installed.
Found in 1 place.
Install
Paste this into your terminal. It downloads exactly the version we scanned, not whatever is newest.
if [ -e ~/.agents/skills/'observability-and-instrumentation' ] || [ -L ~/.agents/skills/'observability-and-instrumentation' ]; then echo 'A skill folder named observability-and-instrumentation already exists — not replacing it' >&2; false; else d=$(mktemp -d) && git clone --quiet --filter=blob:none --no-checkout 'https://github.com/addyosmani/agent-skills' "$d" && git -C "$d" checkout --quiet '39b723ceebf81474d0557c1fecd01eddab585563' -- 'skills/observability-and-instrumentation' && mkdir -p ~/.agents/skills && cp -R "$d"/'skills/observability-and-instrumentation' ~/.agents/skills/'observability-and-instrumentation' && rm -rf "$d"; fi
Codex reads ~/.agents/skills directly. For Claude Code, Cursor, Copilot, Gemini CLI, Antigravity or OpenCode, also link it. For Claude Code: ln -s ~/.agents/skills/'observability-and-instrumentation' ~/.claude/skills/'observability-and-instrumentation' (other agents: ~/.cursor/skills, ~/.copilot/skills, ~/.gemini/skills, ~/.gemini/config/skills, ~/.config/opencode/skills). Or install through the finder skill, which does both.
Badge for your README
The badge for addyosmani/agent-skills shows the score of its lowest-scoring skill.
[](https://zalavijaysinh.github.io/skilltrust/repos/addyosmani/agent-skills/)
Score history
| Date | Version | Score |
|---|
| 2026-11-14 | 39b723c | 80 |
| 2026-11-08 | 301b02b | 80 |
| 2026-11-06 | 301b02b | 80 |