Getting it into your agent
One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.
npx skills add byerlikaya/claude-starter-kit --skill observabilitygit clone --depth 1 https://github.com/byerlikaya/claude-starter-kitWrote this? Show the measurements
A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.
[](https://agentmods.dev/skills/byerlikaya/claude-starter-kit/observability)<a href="https://agentmods.dev/skills/byerlikaya/claude-starter-kit/observability"><img src="https://agentmods.dev/badge/skills/byerlikaya/claude-starter-kit/observability/github.svg" alt="Measured on agentmods" height="20"></a>Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.
<a href="https://agentmods.dev/skills/byerlikaya/claude-starter-kit/observability"><img src="https://agentmods.dev/badge/skills/byerlikaya/claude-starter-kit/observability.svg" alt="Reviewed on agentmods" width="80" height="20"></a>What it costs to keep this loaded
Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.
| Model | Per session | Once invoked |
|---|---|---|
| Fable 5.1 | $0.00062 | $0.00877 |
| Opus 5.5 | $0.00025 | $0.00351 |
| Sonnet 5.5 | $0.00012 | $0.00175 |
| Haiku 4.5 | $0.00006 | $0.00088 |
Grade A, and why
observability scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 1mo ago.
A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.
Nothing flagged
None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.
How it starts
The opening of the file, as written. The whole thing — 53 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Observability
Trigger phrases: "observability", "structured logging", "structured log", "add a trace", "add a metric", "correlation id", "add logging"
Goal: to be able to answer "what happened, where, why" during a production incident by looking at the logs. It is stack-agnostic; when you need a framework-specific library/format, do a web search.
Three signals
- Log — event record (structured/JSON, leveled).
- Metric — numeric time series (request count, latency, error rate, resource usage).
- Trace — a request's journey across services (spans + correlation id).
Checklist
- Logs are structured (JSON/key-value), not string interpolation
- Every log line carries a correlation id (request/trace id)
- Levels are correct: the DEBUG/INFO/WARN/ERROR distinction is meaningful
- No PII/secret is logged (password, token, card, national/ID number, email body)
- Error logs carry context (input summary, user/resource id — not PII); the stack trace does not leak to the user
- Critical business metric + infrastructure metric are emitted (where applicable)
- The correlation id is propagated across service-to-service calls (header/propagation)
How
- Structured logger — set up/use one whose output is machine-readable (JSON). Search for the library the framework recommends.
- Correlation id: generate it at the entry point (HTTP middleware / message consumer) or take it from the incoming
X-Request-Id/trace header; put it in the log context; propagate it to downstream calls. - Level discipline: INFO = business event, WARN = expected-but-noteworthy, ERROR = needs intervention. DEBUG is off/sampled in production.
- Context fields:
event,correlation_id,user_id(not PII, an opaque id),duration_ms,outcome. Do not embed them in free text. - Metrics: at minimum RED (Rate, Errors, Duration) or USE; plus business-critical counters. Search for the framework's metrics library.
- Trace (in a distributed system): start/end spans, bind the correlation id to the trace id.
What this file has done since we first saw it
Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.
- 1mo ago First seen · 53 lines · 62 tokens per session scan A fc4af1c0fc2a
observability is a skill published in the GitHub repository byerlikaya/claude-starter-kit (24 stars, last pushed 1mo ago), licensed MIT. It adds 62 tokens to every session and 877 once invoked, about $0.0002 per session on Opus 5.5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-30.
Other skills, from other repositories
oracle
Oracle second-model review: bundle prompts/files, debug, refactor, design.
skill-repair
Diagnose and fix failing or degraded skills automatically - systemic-first triage, per-category playbooks, and a verification plan.
self-improve
Improve the agent itself, or audit its recent performance - better skills, prompts, workflows, and config, plus a quality/reliability/memory-hygiene review of what it did and what failed.
posthog-errors
Weekly cross-project error overview from PostHog - enumerates every project the OAuth grant covers, pulls the last 7 days of error-tracking issues per project, ranks them by impact, flags what's new vs ongoing, and sends one digest with per-project totals, the top issues, and a clickable link to a full committed…
aeon-doctor
Static config-correctness linter for this instance - catches the silent-failure class (unquoted schedules, duplicate keys, unconfigured skills, mode typos, broken requires/MCP refs) that no run-based health skill can see. Notifies only on problems.
manage-skills
A maintenance workflow for checking whether project verification skills still cover the code and rules that changed during a session.