skillful-agent-system-builder: Skill for Claude Code

.agents/skills/context-window-management/SKILL.md

context-window-management is a skill for Claude Code, Codex from houarnu166/skillful-agent-system-builder. It costs 41 tokens per session (308 once invoked), scanned A, a copy of context-window-management, MIT.

A guide to selecting and organizing the text an AI model receives when its context window—the amount of information it can process at once—is limited. It covers summarizing, trimming, routing, counting tokens, and prioritizing content.

In plain words
What is it for?
Managing token limits, deciding what to summarize or remove, routing information by size, and placing or preserving the most important context.
Why use it?
Long conversations and documents can exceed limits or bury important details, causing weaker answers and unnecessary usage.

Skill for Claude CodeCodex

Written for no agent in particular: nothing here depends on one. Also seen: installed under .agents/ (shared by several agents).

This is houarnu166/skillful-agent-system-builder's own configuration. It tells Claude Code and Codex how to work on skillful-agent-system-builder itself, so it is not a mod to install elsewhere. Copy it as a starting point and replace the rules that are about this project. Everything skillful-agent-system-builder configures →

Reuse

Borrowing it

Nothing to install: this file belongs to houarnu166/skillful-agent-system-builder. Take a copy, put it at the same path in your own repository, and replace the rules that are about this project with yours.

Copy the file
curl -O https://raw.githubusercontent.com/houarnu166/skillful-agent-system-builder/main/.agents/skills/context-window-management/SKILL.md
Clone the repo
git clone --depth 1 https://github.com/houarnu166/skillful-agent-system-builder

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-management

README.md
[![agentmods](https://agentmods.dev/badge/skills/houarnu166/skillful-agent-system-builder/context-window-management.svg)](https://agentmods.dev/skills/houarnu166/skillful-agent-system-builder/context-window-management)
Your own site
<a href="https://agentmods.dev/skills/houarnu166/skillful-agent-system-builder/context-window-management"><img src="https://agentmods.dev/badge/skills/houarnu166/skillful-agent-system-builder/context-window-management.svg" alt="Measured on agentmods" height="20"></a>
Per session 41 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 308 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 100% copy Near-identical to another mod 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 $0.00041 $0.00308
Opus 5 $0.00020 $0.00154
Sonnet 5 $0.00008 $0.00062
Haiku 4.5 $0.00004 $0.00031

Measured 7d ago against content hash 85ba962196db, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-07, from the pricing page.

Security

Grade A, and why

context-window-management 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 7d 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.

Origin

This is a copy

100% identical to context-window-management — 0 lines differ, which has more behind it and is treated as the original. This page carries a canonical link to it rather than competing with it.

.agents/skills/context-window-management/SKILL.md · 54 lines

What it actually says

Context Window Management

You're a context engineering specialist who has optimized LLM applications handling millions of conversations. You've seen systems hit token limits, suffer context rot, and lose critical information mid-dialogue.

You understand that context is a finite resource with diminishing returns. More tokens doesn't mean better results—the art is in curating the right information. You know the serial position effect, the lost-in-the-middle problem, and when to summarize versus when to retrieve.

Your cor

Capabilities

  • context-engineering
  • context-summarization
  • context-trimming
  • context-routing
  • token-counting
  • context-prioritization

Patterns

Tiered Context Strategy

Different strategies based on context size

Serial Position Optimization

Place important content at start and end

Intelligent Summarization

Summarize by importance, not just recency

Anti-Patterns

❌ Naive Truncation

❌ Ignoring Token Costs

❌ One-Size-Fits-All

Works well with: rag-implementation, conversation-memory, prompt-caching, llm-npc-dialogue

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. 7d ago First seen · 54 lines · 41 tokens per session scan A 85ba962196db

Subscribe to this mod's changes

context-window-management is a skill published in the GitHub repository houarnu166/skillful-agent-system-builder (23 stars, last pushed 7mo ago), licensed MIT. It adds 41 tokens to every session and 308 once invoked, about $0.0002 per session on Opus 5. A static security scan graded it A with 0 findings. It is 100% identical to context-window-management, differing in 0 lines, and is treated as a copy.

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