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 analyze-logsgit 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/analyze-logs)<a href="https://agentmods.dev/skills/hugorcd/evlog/analyze-logs"><img src="https://agentmods.dev/badge/skills/hugorcd/evlog/analyze-logs/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/analyze-logs"><img src="https://agentmods.dev/badge/skills/hugorcd/evlog/analyze-logs.svg" alt="Reviewed on agentmods" width="80" height="20"></a>- NVIDIA SkillSpector warn
SkillSpector: 3 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 53 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 58 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 59 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 | $0.00053 | $0.01904 |
| Opus 5.5 | $0.00021 | $0.00762 |
| Sonnet 5.5 | $0.00011 | $0.00381 |
| Haiku 4.5 | $0.00005 | $0.00190 |
Grade A, and why
analyze-logs 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.
Copies of this mod
1 near-identical copy found in the catalogue:
- analyze-logs — 97% identical, 2 lines differ
How it starts
The opening of the file, as written. The whole thing — 185 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Analyze application logs
Read and analyze structured wide-event logs from the local .evlog/logs/ directory to debug errors, investigate performance issues, and understand application behavior.
When to Use
- User asks to debug an error, investigate a bug, or understand why something failed
- User asks about request patterns, slow endpoints, or error rates
- User asks "what happened" or "what's going on" with their application
- User asks to analyze logs, check recent errors, or review application behavior
- User mentions a specific error message or status code they're seeing
Finding the logs
Logs are written by evlog's file system drain as .jsonl files, organized by date.
Format detection: The drain supports two modes:
- NDJSON (default,
pretty: false): One compact JSON object per line. Parse line-by-line. - Pretty (
pretty: true): Multi-line indented JSON per event. Parse by reading the entire file and splitting on top-level objects (e.g.JSON.parse('[' + content.replace(/\}\n\{/g, '},{') + ']')) or use a streaming JSON parser.
Always check the first few bytes of the file to detect the format: if the second character is a newline or ", it's NDJSON; if it's a space or newline followed by spaces, it's pretty-printed.
Search order. Check these locations relative to the project root:
.evlog/logs/(default)- Any
.evlog/logs/inside app directories (monorepos:apps/*/.evlog/logs/)
Use glob to find log files:
.evlog/logs/*.jsonl
*/.evlog/logs/*.jsonl
apps/*/.evlog/logs/*.jsonl
Files are named by date: 2026-03-14.jsonl. Start with the most recent file.
Programmatic reading: instead of hand-parsing, a small script can use the readers shipped with evlog: readFsLogs() and tailFsLogs() from evlog/fs are async generators that handle both formats, date ordering, and filtering. Prefer them when the project already has evlog installed and the analysis needs more than a quick grep.
Memory drain alternative: some apps use the Memory adapter (evlog/memory) instead of (or alongside) the FS drain, exposing recent events through a dev-only HTTP endpoint via readMemoryLogs(). If .evlog/logs/ is empty but the app wires createMemoryDrain(), query that endpoint instead.
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 · 185 lines · 53 tokens per session scan A 5fc2b350c065
analyze-logs is a skill published in the GitHub repository HugoRCD/evlog (1,895 stars, last pushed 2d ago), licensed MIT. It adds 53 tokens to every session and 1,904 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.
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