skill-timing

skill-timing is a skill for Claude Code, Codex from sfc-gh-myoung/ai_coding_rules. It costs 35 tokens per session (3,916 once invoked), scanned A, original, Apache-2.0.

A tool for creating and repairing Page Object Models, which are shared code descriptions of the buttons, fields, and other elements a browser test uses. It discovers elements in the live app instead of guessing their selectors.

In plain words
What is it for?
Use it to map the live app’s elements into reusable test code, prove that selectors work, repair selectors after the interface changes, and identify elements that cannot be verified.
Why use it?
It keeps test code from breaking because of guessed or outdated element selectors. It limits the model to elements used by actual test cases and leaves unverified elements out.

Skill for Claude CodeCodex

Written for no agent in particular: nothing here depends on one. Also seen: mentions subagents; positional $N argument.

Good fit Use it to map the live app’s elements into reusable test code, prove that selectors work, repair selectors after the interface changes, and identify elements that cannot be verified.

Compare 6 skills from other repositories ↓
Install with agentmods
npx agentmods add skills/sfc-gh-myoung/ai_coding_rules/skill-timing
Install

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.

Any agent
npx skills add sfc-gh-myoung/ai_coding_rules --skill skill-timing
Clone the repo
git clone --depth 1 https://github.com/sfc-gh-myoung/ai_coding_rules

Made for: Claude Code, Codex.

Wrote 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.

agentmods badge for skill-timing

README.md
[![agentmods](https://agentmods.dev/badge/skills/sfc-gh-myoung/ai_coding_rules/skill-timing.svg)](https://agentmods.dev/skills/sfc-gh-myoung/ai_coding_rules/skill-timing)
Your own site
<a href="https://agentmods.dev/skills/sfc-gh-myoung/ai_coding_rules/skill-timing"><img src="https://agentmods.dev/badge/skills/sfc-gh-myoung/ai_coding_rules/skill-timing.svg" alt="Measured on agentmods" height="20"></a>
Per session 35 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 3,916 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. A grade says what 26 rules found in the file — not that it is safe.
Origin original No closer match found in the catalogue.
Token cost

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.

ModelPer sessionOnce invoked
Fable 5.1 $0.00035 $0.03916
Opus 5 $0.00017 $0.01958
Sonnet 5 $0.00007 $0.00783
Haiku 4.5 $0.00003 $0.00392

Measured 8d ago against content hash e449ef2be670, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-08, from the pricing page.

Security

Grade A, and why

skill-timing 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 8d ago.

The scan reads SKILL.md. This mod also ships 5 executable files (scripts/find_python.sh, scripts/skill_timing.py, tests/__init__.py, …), listed below but not scanned — reading those needs a real analyzer, not pattern matching.

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.

skills/skill-timing/SKILL.md · 398 lines

How it starts

The opening of the file, as written. The whole thing — 398 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Skill Timing

Timing instrumentation for skill execution measurement with microsecond precision and anomaly detection.

Quick Start

# Measure a skill execution with checkpoints
Use the skill-timing skill.

skill_name: rule-reviewer
target_file: rules/200-python-core.md
model: claude-sonnet-45
review_mode: FULL
timing_enabled: true

Output: Timing metadata embedded in output file with duration, checkpoints, token costs, and baseline comparison.

Purpose

Enable comprehensive performance measurement and analysis:

  • Wall-clock duration - Microsecond precision from start to end
  • Checkpoints - Intermediate timing points for bottleneck analysis
  • Token tracking - Input/output token counts with cost estimation
  • Anomaly detection - Real-time detection of shortcuts and timeouts
  • Baseline comparison - Compare against historical averages
  • Cross-analysis - Performance across models, agents, and modes

Use this skill when

Use this skill when:

  • Measuring skill execution duration
  • Comparing performance across models or agents
  • Identifying bottlenecks with checkpoints
  • Tracking token consumption and costs
  • Detecting potential agent shortcuts (suspiciously fast execution)
  • Building performance baselines for CI/CD
  • Analyzing historical timing trends

Don't use this skill when:

  • The skill execution is trivial (<5 seconds expected)
  • You're just testing syntax (not measuring actual performance)
  • The skill doesn't produce a file output (timing metadata needs a file to embed in)

Inputs

Required (timing-start)

  • skill_name: string — Name of the skill being timed
  • target_file: path — Target file path
  • model: string — Model slug (e.g., claude-sonnet-45)

Required (timing-end)

  • run_id: hex string (16 chars) — From timing-start output
  • output_file: path — Output file for metadata embedding
  • skill_name: string — Skill name (for recovery if run_id lost)

Optional (timing-end)

  • input_tokens: integer (default: none) — Input token count
  • output_tokens: integer (default: none) — Output token count
  • format: string (default: human) — Output format: human, json, markdown, quiet
  • dimension_timings: JSON array (default: none) — Per-dimension timing data (see schema below)
  • auto_dimension_timings: flag (default: off) — Derive dimension_timings automatically from dim_<name>_start / dim_<name>_end checkpoint pairs. Explicit dimension_timings wins if both are supplied (with WARNING).
  • review_mode: string (default: FULL) — Review mode if applicable

Read the full file on GitHub · 398 lines

Changes

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.

  1. 8d ago First seen · 398 lines · 35 tokens per session scan A e449ef2be670

Subscribe to this mod's changes

skill-timing is a skill published in the GitHub repository sfc-gh-myoung/ai_coding_rules (7 stars, last pushed 1mo ago), licensed Apache-2.0. It adds 35 tokens to every session and 3,916 once invoked, about $0.0002 per session on Opus 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 2026-08-31.

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