Jules vs Junie | agentconfig.ing

Jules vs JunieComparisonUpdated 2026-03-16

SUMMARY

Jules (Agent) uses markdown configuration while Junie (Agent) uses markdown. They differ on 2 of 11 compared features. Both tools provide AI-assisted development but take different approaches to project configuration.

FEATURE COMPARISON

Feature	Jules	Junie	Notes
Config format	markdown	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	Agent	Agent
Schema / structure	Free-form (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	Jules	Junie
Project instructions	AGENTS.md	.junie/guidelines.md
Project instructions	GEMINI.md	AGENTS.md

SIDE-BY-SIDE CODE SAMPLES

Jules

AGENTS.md

markdown

# Agent Instructions

## Project
A Django REST API serving a React frontend.

## Setup
- Python 3.12 with Poetry
- PostgreSQL 15
- Redis for caching and Celery broker

## Key Commands
- poetry run python manage.py runserver
- poetry run pytest
- poetry run mypy .

## Pull Request Guidelines
- Keep PRs focused on a single issue
- Add tests for all new functionality
- Update API docs in docs/api/ if endpoints change
- Run the linter: poetry run ruff check .

## Architecture Notes
- apps/core/ — shared models and utilities
- apps/api/v2/ — current API version
- apps/tasks/ — Celery background tasks

Junie

.junie/guidelines.md

markdown

# Project Guidelines

## Language & Framework
- Kotlin with Spring Boot 3.x
- Gradle with Kotlin DSL
- JDK 21 with virtual threads

## Architecture
- Hexagonal architecture (ports & adapters)
- Domain events for cross-module communication
- CQRS for read-heavy endpoints

## Code Standards
- Follow Kotlin coding conventions
- Use data classes for DTOs
- Prefer sealed classes for domain errors
- Extension functions over utility classes

## Testing
- JUnit 5 with Kotest assertions
- Testcontainers for integration tests
- MockK for mocking (not Mockito)

## Build & Run
- Build: ./gradlew build
- Test: ./gradlew test
- Run: ./gradlew bootRun

KEY DIFFERENCES

1. Hierarchy support

Jules: Supported. Junie: Not supported.

2. Subdirectory scoping

Jules: Supported. Junie: Not supported.

WHICH SHOULD I USE?

Recommendation

Choose based on your IDE/CLI preference. If you use Jules, configure AGENTS.md. If you use Junie, configure .junie/guidelines.md. 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