Aider
Also known as: aider-chat, aider AI, aider pair programmer
Aider is a free, open-source AI pair programming tool that runs in your terminal. It works directly with your git repository, supports all major LLM providers (Anthropic, OpenAI, Google, Ollama, and more), and specializes in multi-file edits with automatic git commits. It is the most popular open-source CLI coding agent.
Agent Information
- Provider
- Paul Gauthier (open source)
- Supported IDEs
- Terminal / CLI
Feature Support Matrix
| Feature | Support Level | Details |
|---|---|---|
| Execution | ||
| Automatic Context Awareness | ⚠️ Partial | Aider builds a repo-map — a high-level index of classes, functions, and signatures across the entire codebase — to give ... |
| Filesystem Access | ✅ Full Support | Aider can create, edit, and delete files across the project. Changes are applied directly to the working directory and o... |
| MCP Server Support | ❌ No Support | Aider does not natively support MCP (Model Context Protocol) servers. It has its own tool/plugin ecosystem distinct from... |
| Editor Integration | ||
| Broad IDE Integration | ❌ No Support | Aider is a terminal-only tool. It has no native IDE plugin or extension. You run it alongside any editor, but there is n... |
| Model Support | ||
| Claude 4 Support | ✅ Full Support | Aider supports Claude Sonnet 4.6 and Claude Opus 4.6 via the Anthropic API. These are the recommended models for best re... |
| Claude 3 Support | ✅ Full Support | Aider supports Claude 3 models (Haiku, Sonnet, Opus) via the Anthropic API using the --model flag. |
| Context Window Management | ✅ Full Support | Aider inherits the context window of whichever LLM is selected. When using Claude Sonnet 4.6 or Opus 4.6, the full 200K ... |
| Debugging | ||
| Console Error Integration | ❌ No Support | Aider operates entirely in the terminal and has no browser integration. It cannot monitor or capture browser console err... |
| Interactive Element Selection | ❌ No Support | Aider is a terminal-only tool with no visual UI or ability to select interactive elements from a web or desktop interfac... |
| Live Web Preview | ❌ No Support | Aider has no built-in web preview. It is a CLI coding tool with no browser or UI rendering capabilities. |
| Configuration | ||
| Dedicated Instruction File | ✅ Full Support | Aider supports CONVENTIONS.md (or any file specified with --read) for persistent project-level instructions. You can als... |
| Fine-Grained Instruction Control | ❌ No Support | Aider does not support file-pattern or directory-scoped instruction rules. Instructions are project-wide via CONVENTIONS... |
| Supports Scoped Instructions | ❌ No Support | Aider applies instructions globally via CONVENTIONS.md or .aider.conf.yml. There is no mechanism for scoping instruction... |
| Planning | ||
| Planner Strategy | ⚠️ Partial | Aider's Architect mode separates planning from execution: a powerful model plans the changes, then a faster/cheaper mode... |
Frequently Asked Questions
Aider is a command-line tool that lets you pair program with an LLM inside your terminal. You add files to the chat context, describe what you want, and Aider applies the changes directly to your code with an automatic git commit. It works with any git repository.
Aider supports a wide range of models: Anthropic (Claude Sonnet 4.6, Opus 4.6, Haiku 4.5), OpenAI (GPT-4.1, GPT-4o, o3), Google (Gemini 2.0 Flash, Gemini 2.0 Pro), DeepSeek, Groq, Ollama (local models), and many others via LiteLLM. You specify the model with the --model flag.
Aider itself is completely free and open-source (Apache 2.0). You pay only for the API usage of the underlying LLM provider you choose (e.g., Anthropic, OpenAI). Using Aider with local models via Ollama incurs no API costs at all.
No. Aider runs entirely in the terminal and is IDE-agnostic. You can use it alongside any editor — VS Code, Vim, Emacs, JetBrains IDEs, etc. Some editors have community-built Aider integrations, but none are required.
Aider uses a repo-map system that builds a high-level map of your entire codebase (classes, functions, signatures) to help the LLM understand the project structure. You add specific files to the chat, and Aider applies coordinated changes across all of them in a single operation.
Yes. By default, Aider creates a git commit after each successful change, with a descriptive commit message generated by the LLM. You can disable this behavior with --no-auto-commits if you prefer to review changes before committing.
Architect mode separates planning from execution: a powerful model (e.g., Claude Opus 4.6) plans the changes, then a faster/cheaper model (e.g., Claude Haiku 4.5) executes the edits. This improves quality while reducing cost for large tasks.
Yes. Aider supports local LLMs via Ollama, LM Studio, and other OpenAI-compatible local servers. This enables fully offline use with no external API calls or costs.
Both are CLI-based coding agents. Claude Code is a proprietary tool from Anthropic, tightly integrated with Claude models only. Aider is open-source and model-agnostic, supporting dozens of LLMs. Aider is free (API costs aside), while Claude Code requires an Anthropic subscription.
Yes. You can create a CONVENTIONS.md or .aider.conf.yml file in your project to provide persistent instructions about coding style, preferred libraries, naming conventions, and other guidelines that Aider will follow in every session.