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 rules/dxheroes/mcp-devtools/rules-for-cursorgit clone --depth 1 https://github.com/DXHeroes/mcp-devtoolsWhat 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 | $0.00577 | $0.00577 |
| Opus 5 | $0.00289 | $0.00289 |
| Sonnet 5 | $0.00115 | $0.00115 |
| Haiku 4.5 | $0.00058 | $0.00058 |
Grade A, and why
rules-for-cursor 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.
How it starts
The opening of the file, as written. The whole thing — 102 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Rules for Writing Cursor Rules
This document provides guidelines for creating and maintaining Cursor IDE rules for the MCP DevTools repository.
@url https://docs.cursor.com/context/rules-for-ai @file .cursor/rules/repository-structure.mdc @file .cursor/rules/ai-assisted-development.mdc
Rule Structure
Each rule file should follow this structure:
---
description: Brief description of what the rule enforces
globs: pattern/to/match/files.ts
alwaysApply: true|false
---
# Rule Title
Brief introduction to the rule and its purpose.
@file path/to/example/file.ts
@file path/to/related/rule.mdc
@url https://relevant-docs-url.com/
## Sections
Content organized into clear sections with examples.
## Examples
```typescript
// Code examples demonstrating the rule
```
Guidelines
-
First Guideline
- Explanation point 1
- Explanation point 2
-
Second Guideline
- Explanation point 1
- Explanation point 2
## Frontmatter Requirements
Every rule must include these frontmatter fields:
1. **description**: A concise one-line description of the rule
2. **globs**: File pattern(s) the rule applies to
3. **alwaysApply**: Whether the rule should automatically apply
## File References
Rules should reference:
1. **Example Files**: Include `@file` references to real examples in the codebase
2. **Related Rules**: Link to related rules with `@file` references
3. **External Documentation**: Link to relevant external documentation with `@url`
## Guidelines for Writing Effective Rules
1. **Be Specific**
- Rules should provide clear, actionable guidance
- Include real examples from the codebase when possible
- Explain both what to do and what to avoid
2. **Organize Content**
- Use clear headings and subheadings
- Group related information together
- Use numbered lists for sequential steps
- Use bullet points for related items
3. **Include Code Examples**
- Provide complete, working examples
- Comment code examples to explain important points
- Show both correct and incorrect patterns
4. **Connect with Other Rules**
- Reference related rules
- Avoid duplicating content across rules
- Ensure consistent guidance across all rules
5. **Keep Updated**
- Review and update rules when project standards change
- Ensure examples remain valid as the codebase evolves
- Add new rules as needed for new patterns or technologies
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 · 102 lines · 577 tokens per session scan A 67d8e9652b7c
rules-for-cursor is a cursor rule published in the GitHub repository DXHeroes/mcp-devtools (13 stars, last pushed 1y ago), licensed MIT. It adds 577 tokens to every session, about $0.0029 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.
Other cursor rules, from other repositories
cursorrules
You are building an AI/ML project with Python. The project uses PyTorch for model training, handles data pipelines with proper validation, tracks experiments systematically, and follows production ML engineering practices. Code is type-hinted, tested, and reproducible.
rule
AI/ML Python development (PyTorch, scikit-learn).
language-agnostic-patterns
Language-agnostic programming patterns: SOLID, design patterns, clean code, and architecture. Load when refactoring, designing abstractions, or reviewing structure — not for everyday syntax.
cursor-tools-mastery
Cursor 3.7 runtime guide: choose the right tool, canvases, Design Mode, /worktree, /best-of-n, Await, and parallel execution where safe.
cursor-agent-orchestration
Cursor 3.7 orchestration guide: when to plan, when to delegate, nested subagents, multi-environment handoffs, /best-of-n, and Await for long-running branches.
fable5-reasoning
Fable 5 reasoning protocols: task interpretation, risk-first decomposition, approach selection, interleaved thinking, hypothesis ledgers, premortems, calibration, and the stuck-strategy ladder. Load for complex, ambiguous, or long-horizon tasks, for debugging strategy, or whenever progress stalls.