tool-specification

tool-specification is a skill for Claude Code, Codex from kangarooking/system-prompt-skills. It costs 151 tokens per session (2,150 once invoked), scanned A, original, MIT.

Tool specification defines how an AI discovers, describes, authorizes, and uses external tools. Tools are connected functions or services, such as APIs, browsers, or file operations.

In plain words
What is it for?
Use it to design tool schemas, permission levels, tool discovery, parallel calls, and delegation to other agents.
Why use it?
It makes tool calls more predictable and helps control which actions are automatic, require approval, or are forbidden.

Skill for Claude CodeCodex

Written for no agent in particular: nothing here depends on one. Also seen: mentions Claude Code; mentions Codex; mentions Gemini CLI.

Good fit Use it to design tool schemas, permission levels, tool discovery, parallel calls, and delegation to other agents.

Compare 6 skills from other repositories ↓
Install with agentmods
npx agentmods add skills/kangarooking/system-prompt-skills/tool-specification
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 kangarooking/system-prompt-skills --skill tool-specification
Clone the repo
git clone --depth 1 https://github.com/kangarooking/system-prompt-skills

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 tool-specification

README.md
[![agentmods](https://agentmods.dev/badge/skills/kangarooking/system-prompt-skills/tool-specification/github.svg)](https://agentmods.dev/skills/kangarooking/system-prompt-skills/tool-specification)
Your own site
<a href="https://agentmods.dev/skills/kangarooking/system-prompt-skills/tool-specification"><img src="https://agentmods.dev/badge/skills/kangarooking/system-prompt-skills/tool-specification/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.

agentmods 80×15 button for tool-specification

Your own site · 80×15
<a href="https://agentmods.dev/skills/kangarooking/system-prompt-skills/tool-specification"><img src="https://agentmods.dev/badge/skills/kangarooking/system-prompt-skills/tool-specification.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 151 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 2,150 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 $0.00151 $0.02150
Opus 5 $0.00076 $0.01075
Sonnet 5 $0.00030 $0.00430
Haiku 4.5 $0.00015 $0.00215

Measured 9d ago against content hash 39cad7d81020, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-09, from the pricing page.

Security

Grade A, and why

tool-specification 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 9d 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.

tool-specification/SKILL.md · 110 lines

How it starts

The opening of the file, as written. The whole thing — 110 lines — stays where its author put it; the contents beside it link to each section on GitHub.

工具定义与集成模式 (Tool Specification)

R — 原文 (Reading)

Claude Code: ToolSearch 用于延迟加载, parallel tool calls, Agent tool 用于子代理委托 Claude Chrome: PURL 紧凑命令模式, 三层行动分类 (Prohibited/Explicit Permission/Regular) GPT-4o: Content Reference System, file_search with citation format ChatGPT Agent Mode: 三通道架构 (analysis/commentary/final), browser+computer+container tools Meta AI: 四个命名空间 (media, browser, meta_1p, container, third_party) with full JSON Schema Grok 4: Custom XML function call format (xai:function_call), code_execution with stateful REPL

I — 方法论骨架 (Interpretation)

工具定义与集成的核心设计模式包含五个正交维度:

  1. 定义格式 (Definition Format): JSON Schema(Meta AI, Claude)、XML(Grok 4 的 xai:function_call)、TypeScript 类型(Codex)——格式选择影响解析效率和可组合性。
  2. 权限门控 (Permission Gating): 三层模型——禁止层(Prohibited,绝不可执行)、显式授权层(Explicit Permission,需用户确认)、常规层(Regular,自动执行)。Claude Chrome 的三层分类是这一模式的典范。
  3. 发现机制 (Discovery Mechanism): 当工具数量庞大时(Jules 25+,Meta AI 四个命名空间),需要延迟加载(Claude Code 的 ToolSearch)或命名空间分组(Meta AI 的 media/browser/meta_1p/container/third_party)。
  4. 并行执行 (Parallel Execution): Claude Code 支持并行工具调用,Gemini CLI 通过子代理委托实现并行调查,ChatGPT Agent 通过三通道架构实现思考与行动的并行。
  5. 生命周期管理 (Lifecycle Management): 工具从发现到执行到结果处理的完整流程。Jules 的 plan/review/submit 三阶段生命周期和 Codex 的 Plan tool with skip rules 是这一模式的代表。

A1 — 案例分析 (Past Application)

案例 1: Claude Chrome 的三层权限门控

  • 问题: 浏览器操作涉及极高安全风险(支付、删除、导航到恶意站点),如何在不牺牲易用性的前提下实现安全控制?
  • 设计模式的使用: 将所有浏览器操作分为三层——Prohibited(如自动填写密码字段,绝不执行)、Explicit Permission(如点击购买按钮,必须用户确认)、Regular(如滚动页面,自动执行)。配合 critical_injection_defense 安全层,形成深度防御。
  • 结论: 三层分类比简单的"允许/禁止"二分法更灵活,既避免了过度限制又守住了安全底线。

案例 2: Meta AI 的四命名空间工具架构

  • 问题: Meta 的工具集横跨媒体生成、浏览器操作、第一方服务和第三方插件,如何管理这种复杂度?
  • 设计模式的使用: 将工具按功能域分为四个命名空间,每个命名空间内的工具共享统一的 JSON Schema 定义和权限策略。这种分组方式使得添加新工具成为局部操作,不影响其他命名空间。
  • 结论: 命名空间分组是工具数量超过 15 个时的必选策略,否则 system prompt 会变得不可维护。

案例 3: Gemini CLI 的子代理委托

  • 问题: 单一代理如何高效处理需要并行调查的复杂编程任务?
  • 设计模式的使用: 实现 codebase_investigator、cli_help、generalist、browser_agent 四种专用子代理。主代理作为编排者,将不同类型的子任务委托给专用子代理并行执行,最后汇总结果。
  • 结论: 子代理委托模式在复杂任务中显著优于单体代理,但需要精心设计子代理间的信息传递机制。

Read the full file on GitHub · 110 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. 9d ago First seen · 110 lines · 151 tokens per session scan A 39cad7d81020

Subscribe to this mod's changes

tool-specification is a skill published in the GitHub repository kangarooking/system-prompt-skills (182 stars, last pushed 4mo ago), licensed MIT. It adds 151 tokens to every session and 2,150 once invoked, about $0.0008 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