
Mcp Builder
- 2 installs
- 132 repo stars
- Updated January 14, 2026
- xenitv1/antigravity-workflows
Principles for building MCP (Model Context Protocol) servers, covering tool design, resource patterns, and project structure.
About
Explains MCP server concepts (tools, resources, prompts) and architecture patterns for building a server. A developer uses it when designing or building an MCP server to connect AI with external tools and data.
- Covers MCP core concepts: tools, resources, and prompts
- Includes a suggested MCP server project structure
Mcp Builder by the numbers
- 2 all-time installs (skills.sh)
- Ranked #13,958 of 16,546 AI & Agent Building skills by installs in the Skillselion catalog
- Data as of Aug 4, 2026 (Skillselion catalog sync)
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| Installs | 2 |
|---|---|
| repo stars | ★ 132 |
| Last updated | January 14, 2026 |
| Repository | xenitv1/antigravity-workflows ↗ |
What it does
Principles for building MCP (Model Context Protocol) servers, covering tool design, resource patterns, and project structure.
Files
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.jsonTransport 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 |
---
7. Security Principles
Input Validation
- Validate all tool inputs
- Sanitize user-provided data
- Limit resource access
API Keys
- Use environment variables
- Don't log secrets
- Validate permissions
---
8. Configuration
Claude Desktop Config
| Field | Purpose |
|---|---|
| command | Executable to run |
| args | Command arguments |
| env | Environment variables |
---
9. Testing
Test Categories
| Type | Focus |
|---|---|
| Unit | Tool logic |
| Integration | Full server |
| Contract | Schema validation |
---
10. Best Practices Checklist
- [ ] Clear, action-oriented tool names
- [ ] Complete input schemas with descriptions
- [ ] Structured JSON output
- [ ] Error handling for all cases
- [ ] Input validation
- [ ] Environment-based configuration
- [ ] Logging for debugging
---
Remember: MCP tools should be simple, focused, and well-documented. The AI relies on descriptions to use them correctly.