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.
npx agentmods add skills/diillson/chatcli/mcp-buildernpx skills add diillson/chatcli --skill mcp-buildergit clone --depth 1 https://github.com/diillson/chatcliWhat 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 | $0.00024 | $0.00772 |
| Opus 5 | $0.00012 | $0.00386 |
| Sonnet 5 | $0.00005 | $0.00154 |
| Haiku 4.5 | $0.00002 | $0.00077 |
Grade A, and why
mcp-builder 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 2d 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.
This is a copy
100% identical to mcp-builder — 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.
How it starts
The opening of the file, as written. The whole thing — 177 lines — stays where its author put it; the contents beside it link to each section on GitHub.
MCP Builder
Principles for building MCP servers.
1. MCP Overview
What is MCP?
Model Context Protocol - standard for connecting AI systems with external tools and data sources.
Core Concepts
| Concept | Purpose |
|---|---|
| Tools | Functions AI can call |
| Resources | Data AI can read |
| Prompts | Pre-defined prompt templates |
2. Server Architecture
Project Structure
my-mcp-server/
├── src/
│ └── index.ts # Main entry
├── package.json
└── tsconfig.json
Transport Types
| Type | Use |
|---|---|
| Stdio | Local, CLI-based |
| SSE | Web-based, streaming |
| WebSocket | Real-time, bidirectional |
3. Tool Design Principles
Good Tool Design
| Principle | Description |
|---|---|
| Clear name | Action-oriented (get_weather, create_user) |
| Single purpose | One thing well |
| Validated input | Schema with types and descriptions |
| Structured output | Predictable response format |
Input Schema Design
| Field | Required? |
|---|---|
| Type | Yes - object |
| Properties | Define each param |
| Required | List mandatory params |
| Description | Human-readable |
4. Resource Patterns
Resource Types
| Type | Use |
|---|---|
| Static | Fixed data (config, docs) |
| Dynamic | Generated on request |
| Template | URI with parameters |
URI Patterns
| Pattern | Example |
|---|---|
| Fixed | docs://readme |
| Parameterized | users://{userId} |
| Collection | files://project/* |
5. Error Handling
Error Types
| Situation | Response |
|---|---|
| Invalid params | Validation error message |
| Not found | Clear "not found" |
| Server error | Generic error, log details |
Best Practices
- Return structured errors
- Don't expose internal details
- Log for debugging
- Provide actionable messages
6. Multimodal Handling
Supported Types
| Type | Encoding |
|---|---|
| Text | Plain text |
| Images | Base64 + MIME type |
| Files | Base64 + MIME type |
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.
- 2d ago First seen · 177 lines · 24 tokens per session scan A d13eb1291ed7
mcp-builder is a skill published in the GitHub repository diillson/chatcli (89 stars, last pushed 3d ago), licensed Apache-2.0. It adds 24 tokens to every session and 772 once invoked, about $0.0001 per session on Opus 5. A static security scan graded it A with 0 findings. It is 100% identical to mcp-builder, differing in 0 lines, and is treated as a copy.
Other skills, from other repositories
pptx
从论文、大纲或结构化文本生成 PowerPoint (.pptx) 演示文稿。Use when 用户需要把一篇论文/文章/大纲做成幻灯片、slides、演示文稿、PPT、deck。Don't use when 只需纯文本总结、生成 Word/PDF、或修改已有 pptx 的单个像素级样式。.
ai-style
当任务是用中文撰写或改写面向读者的文案（产品发布稿、公众号文章、邮件、README 等）， 或用户反馈文字「AI 味太重」「不像人写的」时，加载本 Skill。.
curly-quote-sft
Skill "curly-quote-sft" from bojieli/ai-agent-book, covering 中文技术文档符号与引用规范, 何时加载, 符号定义, 决策优先级 and 正反例约束.
triage
你是当前任务的分诊协调者。先识别用户的全部目标、顺序依赖和验收条件，再按 “事实检索 → 计算/执行 → 写作”顺序逐步请求切换到需要的专业能力。不要替专业 能力完成它的工作，也不要在信息缺失时臆造结果。.
writing
将共享历史中的已验证事实和计算结果整理成符合受众、格式与长度约束的成稿。.
research
用真实检索工具查找可追溯的事实、数据和来源。.