CLIby Aider AI★ 4.3

Aider (CLI)

Open-source terminal pair programmer with full MCP support landed in 2025. The "Cursor for the terminal" with model-agnostic configuration.

Homepage MCP docs Source

Safety & Trust

Delv Safety Grade: A

Score 83/100 · assessed 2026-04-19

Maintainer75

Permissions65

Supply chain85

Transparency95

Incidents100

Aider is a well-established open-source terminal-based AI coding assistant with strong transparency and community adoption. The project has active maintenance, comprehensive documentation, and clean supply chain distribution via PyPI. MCP support landed in 2025 as a first-class feature. The main safety consideration is that Aider operates as a CLI tool with inherent filesystem write access and git integration, meaning it can modify your codebase directly. As an MCP client host, it inherits the permissions of whatever MCP servers you configure, so safety depends heavily on your server choices. The maintainer is a solo developer (Paul Gauthier) rather than a large organisation, but the project has substantial community traction and transparent development. No known security incidents. The model-agnostic design and local-first architecture are positive signals.

Green flags

Fully open source with 20k+ GitHub stars and active development
Distributed via PyPI with standard versioning and dependency management
Comprehensive documentation including security considerations
MCP support is complete for tools, not a half-implementation
Model-agnostic design reduces vendor lock-in

Red flags

Solo maintainer with bus factor risk despite community size
Direct filesystem write access to entire codebase by design
Inherits all permissions from configured MCP servers without sandboxing
Git integration means potential for unintended commits or pushes

Permissions requested

Read filesWrite filesDelete filesOutbound networkShell executeRepo readRepo writeExternal LLM call

Assessed by Delv Editorial using public metadata. Grades are advisory and update as the ecosystem changes. They do not replace your own review of permissions and code before granting an agent access to sensitive systems.

MCP capabilities

Tools
Resources
Prompts
Sampling

Platforms

macOSLinuxWindows

Config location

Configured via Aider config file or .mcp.json

Review

I switched to Aider after months of bouncing between Cursor and Claude Desktop, and it's become my default for anything that doesn't need a GUI. The MCP support landed in early 2025 and it's genuinely complete for tools - no half-measures. You get the same server ecosystem as Claude Desktop, but in a terminal that already understands your codebase. Configuration is straightforward. Drop an `.aider.conf.yml` in your project root or use the global `.mcp.json` format. I run filesystem, postgres, and github servers simultaneously without thinking about it. The model-agnostic setup means I can swap between Claude, GPT-4, and local models mid-session without reconfiguring servers. That flexibility matters when you're prototyping with a cheap model then switching to something capable for the hard bits. The workflow I keep returning to: `aider --model claude-3-5-sonnet-20241022` in a project directory, MCP servers auto-connect, and I'm editing code with full context from my database schema and git history. The diff-based editing is cleaner than most GUI implementations - you see exactly what changed, approve or reject, and move on. No mystery edits buried in a chat sidebar. Rough edges exist. Resources and prompts aren't supported yet, which rules out some of the fancier MCP servers that lean on those capabilities. The terminal UI won't win design awards - it's functional, not beautiful. If you need side-by-side previews or rich formatting, this isn't your tool. And while the docs cover MCP setup, you'll need to understand how Aider's own config system works first. It's not complex, but it's another layer. Performance is solid. I've had sessions running for hours with multiple MCP servers active and haven't seen slowdowns. The git integration is tighter than anything else I've used - automatic commits, branch management, and proper context about what changed when. That matters more than it sounds when you're iterating fast. The open-source angle is real. When I wanted to understand how it handles MCP tool calls, I read the code. When a server misbehaved, I could see exactly what Aider was sending. That transparency beats a black box every time.

Verdict

Best MCP client for developers who live in the terminal and want proper git integration. If you need resources/prompts support or prefer visual interfaces, wait for updates or look at Claude Desktop.

Good at

Model-agnostic - swap between Claude, GPT-4, local models without reconfiguring MCP servers
Git integration is genuinely better than GUI alternatives - automatic commits, clean diffs, branch awareness
Open source with readable code - you can debug MCP issues yourself
Handles multiple simultaneous MCP servers without performance issues
Config via project files or global .mcp.json - works how you'd expect

Watch out

No support for MCP resources or prompts yet - limits which servers you can use fully
Terminal-only UI won't suit everyone - no previews, no rich formatting
Requires understanding both Aider's config system and MCP setup
Documentation assumes you're comfortable with CLI tools and config files
Not ideal for collaborative editing or showing work to non-technical stakeholders