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.
git clone --depth 1 https://github.com/lazylagom/context-compose-mcpWrote 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.
[](https://agentmods.dev/rules/lazylagom/context-compose-mcp/development-guidelines)<a href="https://agentmods.dev/rules/lazylagom/context-compose-mcp/development-guidelines"><img src="https://agentmods.dev/badge/rules/lazylagom/context-compose-mcp/development-guidelines/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.
<a href="https://agentmods.dev/rules/lazylagom/context-compose-mcp/development-guidelines"><img src="https://agentmods.dev/badge/rules/lazylagom/context-compose-mcp/development-guidelines.svg" alt="Reviewed on agentmods" width="80" height="20"></a>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.
| Model | Per session | Once invoked |
|---|---|---|
| Fable 5.1 | $0.00000 | $0.00512 |
| Opus 5.5 | $0.00000 | $0.00205 |
| Sonnet 5.5 | $0.00000 | $0.00102 |
| Haiku 4.5 | $0.00000 | $0.00051 |
Grade A, and why
development-guidelines 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 1mo 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.
What it actually says
Development Guidelines
TypeScript Coding Standards
- Type Safety: Explicit type definitions for all functions and variables
- Strict Mode: Enable strict type checking in tsconfig.json
- Type Guards: Utilize Zod schemas for runtime validation
Code Quality
ESLint Configuration
- Configuration files: eslint.config.js and .eslintrc.json
- Apply TypeScript ESLint rules
- Auto-fix:
npm run lint:fix
Prettier Formatting
- Configuration file: .prettierrc
- Auto-formatting:
npm run format - Format check:
npm run format:check
Biome Integration
- Configuration file: biome.json
- Provides fast linting and formatting
File Structure Rules
src/ Directory Structure
src/
├── cli/ # CLI related code
├── core/ # Core business logic
├── schemas/ # Zod schema definitions
└── types/ # TypeScript type definitions
mcp-server/ Directory
- MCP server implementation
- Uses FastMCP framework
- mcp-server/server.ts main file
Testing Strategy
Vitest Unit Tests
- Configuration file: vitest.config.ts
- Execution:
npm test - Write tests for all utility functions and core logic
Playwright E2E Tests
- Configuration file: playwright.config.ts
- Integration tests for CLI interface and MCP server
Build and Deployment
Build Process
- TypeScript compilation:
npm run build - Type checking:
npm run type-check - Output directory:
dist/
Package Deployment
- NPM public package:
npm run publish-public - Version management: Apply semantic versioning in package.json
Dependency Management
- Runtime Dependencies: Keep to minimum
- Development Dependencies: Development tools and testing frameworks
- Use pnpm: Lock dependencies with pnpm-lock.yaml
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.
- 1mo ago First seen · 73 lines · 0 tokens per session scan A 22559b85aec5
development-guidelines is a cursor rule published in the GitHub repository lazylagom/context-compose-mcp (1 stars, last pushed 1y ago), licensed MIT. It costs nothing until one of its globs matches a file; then it loads 512 tokens. 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 2026-08-31.
Other cursor rules, from other repositories
auth
Auth architecture, middleware chain, and auth-specific coding standards.
tableau-mcp
Tableau MCP project context, architecture overview, and core principles.
tools
MCP tool development patterns — factory pattern, base class, callbacks, and descriptions.
testing
Testing standards — Vitest framework, test organization, mocking patterns.
code-optimization
Guidelines for optimizing duplicate and poorly structured code.
implementation-workflow
Required plan-first workflow for any implementation request (steps 1–5).