evlog is a TypeScript-first logging and observability project built around wide events and structured errors across runtimes. It is intended to help developers record application behavior and diagnose failures.
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 HugoRCD/evlog --skill review-logging-patternsgit clone --depth 1 https://github.com/HugoRCD/evlogWrote 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/hugorcd/evlog/review-logging-patterns)<a href="https://agentmods.dev/skills/hugorcd/evlog/review-logging-patterns"><img src="https://agentmods.dev/badge/skills/hugorcd/evlog/review-logging-patterns/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/hugorcd/evlog/review-logging-patterns"><img src="https://agentmods.dev/badge/skills/hugorcd/evlog/review-logging-patterns.svg" alt="Reviewed on agentmods" width="80" height="20"></a>- NVIDIA SkillSpector warn
SkillSpector: 5 findings, up to medium
These are SkillSpector’s own severities. On a checked sample its high-severity flags on skills were ~96% false positives — a documented command, a public API, a “never do X” rule — so we show them as a caution to read, not a verdict. Why →
- medium MCP Rug Pull · line 67 npx commands without a version suffix (e.g. @1.0.0) create a rug-pull risk if the upstream server is compromised and publishes a malicious update.Fix: Pin the version: npx @scope/[email protected]
- medium MCP Rug Pull · line 70 npx commands without a version suffix (e.g. @1.0.0) create a rug-pull risk if the upstream server is compromised and publishes a malicious update.Fix: Pin the version: npx @scope/[email protected]
- medium MCP Rug Pull · line 83 npx commands without a version suffix (e.g. @1.0.0) create a rug-pull risk if the upstream server is compromised and publishes a malicious update.Fix: Pin the version: npx @scope/[email protected]
- medium MCP Rug Pull · line 84 npx commands without a version suffix (e.g. @1.0.0) create a rug-pull risk if the upstream server is compromised and publishes a malicious update.Fix: Pin the version: npx @scope/[email protected]
- medium MCP Rug Pull · line 92 npx commands without a version suffix (e.g. @1.0.0) create a rug-pull risk if the upstream server is compromised and publishes a malicious update.Fix: Pin the version: npx @scope/[email protected]
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 | $0.00197 | $0.11229 |
| Opus 5.5 | $0.00079 | $0.04492 |
| Sonnet 5.5 | $0.00039 | $0.02246 |
| Haiku 4.5 | $0.00020 | $0.01123 |
Grade A, and why
review-logging-patterns scanned grade A with 1 finding 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.
Makes network callslowCapability
Not a fault in itself. Listed so you know the mod talks to something, and to what.
export default async function fetch(request: Request) { Copies of this mod
1 near-identical copy found in the catalogue:
- review-logging-patterns — 97% identical, 12 lines differ
How it starts
The opening of the file, as written. The whole thing — 1,224 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Review logging patterns
Review and improve logging patterns in TypeScript/JavaScript codebases. Transform scattered console.logs into structured wide events and convert generic errors into self-documenting structured errors.
When to Use
- Setting up evlog in a new or existing project (any supported framework)
- Reviewing code for logging best practices
- Converting console.log statements to structured logging
- Improving error handling with better context
- Configuring log draining, sampling, or enrichment
Quick Reference
| Working on... | Resource |
|---|---|
| Setup (CLI) | evlog init — wire evlog into the project |
| Project conventions (CLI) | evlog agents — write the evlog block into the project's AGENTS.md |
| Coverage map (CLI) | evlog map — score dark entry points |
| CI gating (CLI) | evlog map --min-score / --baseline — gate regressions |
| Wide events patterns | references/wide-events.md |
| Error handling | references/structured-errors.md |
| Code review checklist | references/code-review.md |
| Drain pipeline | references/drain-pipeline.md |
| Audit logs | build-audit-logs skill + docs |
Audit logs
For security-sensitive actions (auth, billing, admin, data export), use evlog's audit layer: a typed audit field on wide events, not a parallel logger. See the build-audit-logs skill for end-to-end setup (log.audit, withAudit, denials, auditEnricher, auditOnly, signed, mockAudit).
What ships with it
4 files beside SKILL.md in the same directory: the scripts, references and assets a skill reads on demand. Not counted in the per-session cost; read them before you install if any of them is executable.
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 Changed 71c27b59d2ac
- 1mo ago First seen · 1,224 lines · 197 tokens per session scan A bf2270c3f1ad
review-logging-patterns is a skill published in the GitHub repository HugoRCD/evlog (1,895 stars, last pushed 3d ago), licensed MIT. It adds 197 tokens to every session and 11,229 once invoked, about $0.0008 per session on Opus 5.5. A static security scan graded it A with 1 finding (makes network calls). No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-30.
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