Aider AI Coding Assistant

This skill helps you set up and use Aider, an AI pair programming tool that can edit code directly in your local git repository using various AI models.

What This Skill Does

Aider is a command-line tool that lets you pair program with AI to edit code in your local git repository. It can:

Configuration Overview

Based on the SLU.ad static site configuration, here are the key settings:

Model Configuration

Git Integration

File Management

Step-by-Step Instructions

1. Initial Setup

Create a `.aider.conf.yml` file in your git repository root with these essential settings:

```yaml

Main model selection

model: 4o

Edit format - use diff for precise changes

edit-format: diff

Git settings

auto-commits: false # Manual control over commits

watch-files: true # Enable file watching for AI comments

Auto-lint after changes

auto-lint: true

```

2. Starting Aider

**Basic usage:**

```bash

aider <file1> <file2> <file3>

```

**With read-only reference files:**

```bash

aider --file main.py --read utils.py --read config.json

```

**Single message mode (non-interactive):**

```bash

aider --message "Add error handling to the login function"

```

3. Using Aider in Chat Mode

Once in the Aider chat interface:

**Common commands:**

4. File Watching Mode

When `watch-files: true` is enabled:

1. Add special comments to your code files:

```python

AIDER: Add input validation to this function

def process_user_data(data):

return data

```

2. Aider will detect these comments and suggest or make changes automatically

5. Linting and Testing

**Configure linting per language:**

```yaml

lint-cmd:

- "python: flake8 --select=E,W"

- "javascript: eslint"

```

**Configure testing:**

```yaml

test-cmd: pytest

auto-test: false # Set to true for automatic testing after changes

```

6. Working with Different Models

**Switch models easily:**

```yaml

model: 4o # GPT-4o

model: sonnet # Claude 3.5 Sonnet

model: deepseek # DeepSeek Chat

model: o1-mini # OpenAI o1-mini

```

**Use model aliases for custom models:**

```yaml

alias:

- "fast=gpt-4o-mini"

- "smart=claude-3-5-sonnet-20241022"

```

7. Advanced Configuration

**Map tokens (for repository understanding):**

```yaml

map-tokens: 2048 # Tokens for repo map

map-refresh: auto # auto, always, files, manual

```

**History and logging:**

```yaml

chat-history-file: .aider.chat.history.md

restore-chat-history: true

llm-history-file: .aider.llm.history

```

**Output customization:**

```yaml

dark-mode: true # or light-mode: true

pretty: true

stream: true

show-diffs: true # Show diffs when committing

```

Usage Examples

Example 1: Refactor a Function

```bash

aider src/main.py

In chat:

"Refactor the calculate_total function to be more readable and add type hints"

```

Example 2: Add Feature Across Multiple Files

```bash

aider --file src/api.py --file src/models.py --file tests/test_api.py

In chat:

"Add a new endpoint for user profile updates with validation and tests"

```

Example 3: Fix Issues Found by Linter

```bash

aider --lint

Automatically lints dirty files and offers to fix issues

```

Example 4: Batch Processing with Message File

```bash

echo "Add docstrings to all public functions" > instructions.txt

aider --message-file instructions.txt src/*.py

```

Important Constraints

1. **Git Repository Required**: Aider requires a git repository by default (disable with `git: false`)

2. **API Keys**: Store API keys in `.env` file in git root:

```env

OPENAI_API_KEY=sk-...

ANTHROPIC_API_KEY=sk-ant-...

```

3. **Model-Specific Edit Formats**: Some models work better with specific edit formats:

- `diff` - Best for most models, precise changes

- `architect` - For high-level planning

- `editor-diff` - For editor models

4. **File Size Limits**: Large files may exceed context windows. Use `--read` for reference files you don't need to edit.

5. **Auto-commits Off**: With `auto-commits: false`, you must manually commit changes. This gives you review control but requires discipline.

Best Practices

1. **Start Small**: Begin with one or two files, add more as needed

2. **Use Read-Only Files**: Reference configuration and documentation with `--read`

3. **Review Diffs**: Always review changes before committing

4. **Commit Often**: Even with auto-commits off, commit working states frequently

5. **Use Descriptive Messages**: Let Aider generate commit messages, but review them

6. **Watch Mode for Large Refactors**: Use file watching for systematic improvements

7. **Test Integration**: Configure `test-cmd` and `lint-cmd` for quality assurance

Troubleshooting

**Aider won't start:**

**Changes not being made:**

**Performance issues:**