Fusion vs PearAI | agentconfig.ing

Fusion vs PearAIComparisonUpdated 2026-03-16

SUMMARY

Fusion (IDE) uses mdc configuration while PearAI (Editor) uses markdown. They differ on 3 of 11 compared features. Both tools provide AI-assisted development but take different approaches to project configuration.

FEATURE COMPARISON

Feature	Fusion	PearAI	Notes
Config format	mdc	markdown
Hierarchy support	✗	✗	Whether config files can be placed at multiple directory levels
Global config	✗	✗	User-wide configuration outside any project
Project config	✓	✓
Subdirectory scoping	✗	✗	Config files in subdirectories that apply only to that subtree
File inclusion / imports	✗	✗	Ability to include or reference other files from config
Ignore file	✗	✗
IDE integration	✓	Editor
Schema / structure	Hybrid (MDC frontmatter + Markdown)	Free-form (Markdown)	Whether config uses structured schema or free-form content
Git committed	✓	✓	Whether primary config files are intended to be version-controlled
Encoding	UTF-8	UTF-8

FILE MAPPING

Purpose	Fusion	PearAI
Project rules	.builder/rules/*.mdc	.pearai/rules
Project instructions	AGENTS.md	AGENTS.md

SIDE-BY-SIDE CODE SAMPLES

Fusion

.builder/rules/*.mdc

mdc

---
description: React component conventions
globs: src/components/**/*.tsx
alwaysApply: false
---

# React Component Rules

## Structure
- Use functional components with TypeScript
- Define props interface above the component
- Export components as named exports

## Styling
- Use the project design system tokens for spacing and colors
- Prefer utility classes over custom CSS
- Keep component-specific styles colocated

## Patterns
- Wrap async data in Suspense boundaries
- Use forwardRef for reusable interactive components
- Keep components under 150 lines; extract hooks for logic

## Accessibility
- All interactive elements need aria-labels
- Use semantic HTML elements (nav, main, section)
- Ensure keyboard navigation works for custom widgets

PearAI

.pearai/rules

markdown

# PearAI Project Rules

## Framework
- Next.js 15 App Router with TypeScript
- Drizzle ORM with PostgreSQL
- TailwindCSS v4 for styling

## Patterns
- Use server actions for mutations
- Colocate loading.tsx and error.tsx with page routes
- Prefer RSC; add "use client" only when needed

## Naming
- Components: PascalCase (UserProfile.tsx)
- Utilities: camelCase (formatDate.ts)
- Database tables: snake_case

## Dependencies
- Do NOT add new dependencies without asking
- Use date-fns for date manipulation
- Use zod for all validation

## Commands
- Dev: pnpm dev
- Build: pnpm build
- Lint: pnpm lint

KEY DIFFERENCES

1. Config format

Fusion: mdc. PearAI: markdown.

2. IDE integration

Fusion: Supported. PearAI: Editor.

3. Schema / structure

Fusion: Hybrid (MDC frontmatter + Markdown). PearAI: Free-form (Markdown).

WHICH SHOULD I USE?

Recommendation

Choose based on your IDE/CLI preference. If you use Fusion, configure .builder/rules/*.mdc. If you use PearAI, configure .pearai/rules. Many projects include config files for multiple tools so each team member can use their preferred editor.

PORTABILITY TIP

sync-instructions.sh

bash

# Maintain a single source of truth:
cp AI-INSTRUCTIONS.md CLAUDE.md
cp AI-INSTRUCTIONS.md .cursorrules
cp AI-INSTRUCTIONS.md AGENTS.md