context-window-to-skill

context-window-to-skill is a skill for Claude Code, Codex from forefy/.context. It costs 35 tokens per session (279 once invoked), scanned A, original, MIT.

A process for turning a completed conversation into a reusable coding-agent skill. It captures lessons, problems, and useful instructions from the work.

In plain words
What is it for?
Use it to identify what a future agent should know, propose core instructions, and create a skill for later use.
Why use it?
It prevents the same trial and error from being repeated on similar tasks.

Skill for Claude CodeCodex

Written for no agent in particular: nothing here depends on one. Also seen: reads .claude/ paths.

Good fit Use it to identify what a future agent should know, propose core instructions, and create a skill for later use.

Compare 6 skills from other repositories ↓
Install with agentmods
npx agentmods add skills/forefy/.context/context-window-to-skill
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 forefy/.context --skill context-window-to-skill
Clone the repo
git clone --depth 1 https://github.com/forefy/.context

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 context-window-to-skill

README.md
[![agentmods](https://agentmods.dev/badge/skills/forefy/.context/context-window-to-skill.svg)](https://agentmods.dev/skills/forefy/.context/context-window-to-skill)
Your own site
<a href="https://agentmods.dev/skills/forefy/.context/context-window-to-skill"><img src="https://agentmods.dev/badge/skills/forefy/.context/context-window-to-skill.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 279 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. Third-party audits
  • NVIDIA SkillSpector warn 7 Sept 2026
SkillSpector: 1 finding, 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 Rogue Agent · line 7
    Skill establishes unauthorized persistence across sessions via cron jobs, startup scripts, or state files. Session persistence allows an attacker to maintain access beyond the current interaction.
    Fix: Remove any persistence mechanisms (cron jobs, startup scripts, state files). Skills should not maintain state across sessions without explicit user consent.
How audits are shown
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 $0.00279
Opus 5 $0.00017 $0.00139
Sonnet 5 $0.00007 $0.00056
Haiku 4.5 $0.00003 $0.00028

Measured 8d ago against content hash 968f49ad0796, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-08, from the pricing page.

Security

Grade A, and why

context-window-to-skill 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.

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/generic-utils/context-window-to-skill/SKILL.md · 18 lines

What it actually says

Use Case:

User had finished working on his feature or task successfully, but had to tweak lots of stuff in the behavior of the agent prior to completion - we now want to create a skill that in the next time will make this task a breeze

Steps:

  1. Analyze conversation and understand fully what the user tried to achieve
  2. Analyze where were the pitfalls, user frustrations, and what pre-information would have made the results quicker to get with the most quality
  3. Print to the user 10 (or more) top items you think are the core points to base the new skill upon
  4. Consult with the user if questions still remain
  5. Create a skill and place it on the ~/.claude/skills/ directory. comply to agent skill format and https://code.claude.com/docs/en/skills

Results:

  • Working new skill, that next time would do the job much better with all the tweaks needed to perfect it based on learned conversation and observation
  • New skill should be reusable (e.g. think fixes also for future usecases other than the single one the user encountered)
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 · 18 lines · 35 tokens per session scan A 968f49ad0796

Subscribe to this mod's changes

context-window-to-skill is a skill published in the GitHub repository forefy/.context (144 stars, last pushed yesterday), licensed MIT. It adds 35 tokens to every session and 279 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 2026-08-30.

Related

Other skills, from other repositories

eresus-manual-security-audit

Elite manual security code review skill for deep, adversarial vulnerability hunting and exploit-chain discovery. Trigger when the user asks to: "do a deep security audit", "manual code review", "find exploit chains", "hunt for logic bugs", "red-team this codebase", "do an offensive security review", "review this like…

EresusSecurity/appsec-skills · 145 tokens

eresus-sast-scanner

General-purpose Static Application Security Testing (SAST) skill for code vulnerability analysis. Trigger when the user asks to: "analyze code for vulnerabilities", "review code security", "find security bugs", "do a SAST scan", "check for [vulnerability type] in code", "audit source code", or requests a security code…

EresusSecurity/appsec-skills · 100 tokens

eresus-php-audit

Deep PHP-specific security audit skill covering injection, deserialization, file operations, auth bypass, POP chain discovery, and CMS-specific patterns. Trigger when auditing PHP code: "audit this PHP app", "find PHP security issues", "check Laravel/WordPress for vulnerabilities", "PHP SAST review", "check for PHP…

EresusSecurity/appsec-skills · 92 tokens

eresus-python-audit

Deep Python-specific security audit skill with 50+ vulnerability class coverage across 7 categories. Trigger when auditing Python code: "audit this Python app", "find Python security issues", "check Flask/Django for vulnerabilities", "Python SAST review", "check for pickle vulnerabilities", "review this FastAPI code".…

EresusSecurity/appsec-skills · 101 tokens

eresus-remediator

Security remediation skill for fixing confirmed or likely SAST findings in source code. Trigger when the user asks to: "fix a vulnerability", "patch this security bug", "remediate SAST findings", "harden this endpoint", "make this auth flow safe", or wants code changes that remove a confirmed security issue while…

EresusSecurity/appsec-skills · 84 tokens

eresus-pr-security-review

Security-focused pull request and diff review skill for finding newly introduced vulnerabilities, risky regressions, and missing security tests in changed code. Trigger when the user asks to: "review this PR for security", "check this diff for vulns", "do a security code review", "audit changed files", or wants…

EresusSecurity/appsec-skills · 90 tokens