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.
Borrowing it
Nothing to install: this file belongs to HugoRCD/evlog. Take a copy, put it at the same path in your own repository, and replace the rules that are about this project with yours.
curl -O https://raw.githubusercontent.com/HugoRCD/evlog/main/.agents/skills/create-map-rule/SKILL.mdgit 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/create-map-rule)<a href="https://agentmods.dev/skills/hugorcd/evlog/create-map-rule"><img src="https://agentmods.dev/badge/skills/hugorcd/evlog/create-map-rule/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/create-map-rule"><img src="https://agentmods.dev/badge/skills/hugorcd/evlog/create-map-rule.svg" alt="Reviewed on agentmods" width="80" height="20"></a>- NVIDIA SkillSpector warn
SkillSpector: 2 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 Agent Snooping · line 154 Skill enumerates or reads other installed skills. Access to other skills' SKILL.md files or the skills directory reveals prompt instructions, capabilities, and secrets that should be invisible to peer skills.Fix: Remove all code or instructions that list or read other skills' files or directories. Skills should operate independently; cross-skill access is a privilege escalation.
- medium Agent Snooping · line 154 Skill enumerates or reads other installed skills. Access to other skills' SKILL.md files or the skills directory reveals prompt instructions, capabilities, and secrets that should be invisible to peer skills.Fix: Remove all code or instructions that list or read other skills' files or directories. Skills should operate independently; cross-skill access is a privilege escalation.
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 | $0.00074 | $0.02639 |
| Opus 5.5 | $0.00030 | $0.01056 |
| Sonnet 5.5 | $0.00015 | $0.00528 |
| Haiku 4.5 | $0.00007 | $0.00264 |
Grade A, and why
create-evlog-map-rule 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 2mo 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 — 159 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Create an evlog map Rule (or Framework Adapter)
Extend the coverage scanner in @evlog/cli. Two kinds of extension:
- A rule: a new question asked of every entry point (
packages/cli/src/lib/map/rules/). This is the common case. - A framework adapter: teach
evlog mapto find entry points in a new framework (packages/cli/src/lib/map/adapters/). Rarer and heavier; see the last section.
PR Title
feat(cli): add the {id} map rule
The cli scope already exists, so no scope registration is needed.
Requirement or opportunity? Decide first
This is the design decision everything else follows from (see apps/docs/content/3.cli/3.rules.md for the published contract):
| Requirement | Opportunity | |
|---|---|---|
| Effect on the score | Costs weight points when it fails |
None, ever — the type forbids a weight |
| When it appears | Whenever it applies | Only when the project already uses the feature (appliesTo.when gated on project.features / project.pairable) |
| In the report | FIX FIRST / THEN |
GOING FURTHER |
Can fail a CI gate (--min-score, --baseline) |
Yes | No |
Guiding principle (from error-catalog.ts): a rule that fires on perfectly good code is policing, not helping. Opportunities must be gated on a signal that makes the case on its own (duplication, an installed package used without its evlog integration), never on "you could adopt a feature you don't use".
Current requirements: wide-event (40), audit (25), structured-errors (20), page-error-handling (20), context (15), error-handling (15). Current opportunities: error-catalog, audit-coverage, ai-logging, auth-identity.
Touchpoints Checklist (rule)
| # | File | Action |
|---|---|---|
| 1 | packages/cli/src/lib/map/rules/{id}.ts |
Create the rule (one exported const) |
| 2 | packages/cli/src/lib/map/rules/index.ts |
Import + one line in REGISTRY |
| 3 | packages/cli/src/lib/map/types.ts |
Add the id to the CheckId union (a type assert in index.ts fails the build if the registry and union drift) |
| 4 | packages/cli/test/map/rules.test.ts |
Add cases (the file has an ESLint-RuleTester-style Case harness — runRuleSet exercises one rule in isolation) |
| 5 | apps/docs/content/3.cli/3.rules.md |
Add a row to the Requirements or Opportunities table + a ### {title} section |
| 6 | apps/docs/content/3.cli/4.scoring.md |
Requirements only: reflect the new weight in the scoring explanation |
| 7 | skills/review-logging-patterns/references/code-review.md |
Add a row to the matching rules table |
| 8 | .changeset/{id}-map-rule.md |
Changeset for "@evlog/cli": minor |
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.
- 2mo ago First seen · 159 lines · 74 tokens per session scan A 6eee3d6e2e4c
create-evlog-map-rule is a skill published in the GitHub repository HugoRCD/evlog (1,903 stars, last pushed 12d ago), licensed MIT. It adds 74 tokens to every session and 2,639 once invoked, about $0.0003 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.
create-evlog-map-rule compared with skills from other repositories
| Mod | Type | Stars | Last push | Licence | Scan | Tokens | Works with |
|---|---|---|---|---|---|---|---|
| create-evlog-map-ruleHugoRCD/evlog | Skill | 1.9k | 12d ago | MIT | A | 74 | Claude Code, Codex |
| gh-issueapache/skywalking-banyandb | Skill | 355 | today | Apache-2.0 | A | 91 | Claude Code |
| gh-pull-requestapache/skywalking-banyandb | Skill | 355 | today | Apache-2.0 | A | 37 | Claude Code |
| vendor-updateapache/skywalking-banyandb | Skill | 355 | today | Apache-2.0 | A | 95 | Claude Code |
| bydbqlapache/skywalking-banyandb | Skill | 355 | today | Apache-2.0 | A | 71 | Claude Code |
| frontmcp-observabilityagentfront/frontmcp | Skill | 148 | yesterday | Apache-2.0 | A | 196 | Claude Code, Codex |
| compilingapache/skywalking-banyandb | Skill | 355 | today | Apache-2.0 | A | 31 | Claude Code |