OHarness vs Aider
Choose Aider if you want pair programming built around git — automatic commits, `/undo`, a repository map — with a light footprint. Choose OHarness if you need an agent with MCP tools, subagents, permission rules and a browser or desktop UI.
Aider’s side checked against its own documentation on . Sources are listed below.
Side by side
| OHarness | Aider | |
|---|---|---|
| Form factor | Terminal UI, browser UI, desktop app (macOS) and a headless runner — one engine | Terminal chat; editor integration through a comment-driven watch mode; Python API |
| Licence and source | Free to use; npm packages MIT. Source repository not public yet | Apache-2.0, source public |
| Models | Anthropic, OpenAI and Gemini natively; any OpenAI-compatible endpoint; 30+ catalogued providers | OpenAI, Anthropic, Gemini, DeepSeek, Groq, OpenRouter, Bedrock, Vertex and more |
| Local models | Ollama, LM Studio and vLLM built in, no key | Ollama, and any OpenAI-compatible local server |
| Switching mid-session | /model mid-session; history is vendor-neutral, nothing converted | /model, /editor-model, /weak-model |
| MCP | Yes — stdio and Streamable HTTP, with OAuth for remote servers | Not documented |
| Permissions | Five modes plus allow/ask/deny rules in user, project and local scopes; deny beats bypass | Confirms before acting; --yes auto-confirms; every change is a git commit |
| Sandbox | No OS sandbox — a policy gate on tool arguments. Use a container for confinement | Not documented |
| Subagents | Yes — isolated contexts, run in parallel | No; architect/editor mode splits one task across two models |
| Headless | oharness-headless, JSONL on stdout | --message with --yes; no JSON output documented |
| Price | Free with your own key or a local model; optional hosted plan | Free, your own key, no account |
Where Aider is stronger
- Git is the workflow: every change is committed with a message, and
/undoreverts it. - A repository map gives the model a compact view of the whole codebase.
- Runs linters and tests and fixes what they report.
- Public source, and years of use behind it. Its own model leaderboards are widely cited.
Where OHarness is stronger
- MCP servers, subagents, hooks and skills — Aider's docs mention none of these.
- Allow/ask/deny rules per tool and argument, stored per project.
- Headless runs emit JSONL events a CI job can parse.
- Browser and desktop UIs on the same engine.
Which to choose
Aider, if you want a focused pair programmer that treats git history as the undo stack and stays out of the way.
OHarness, if you want an agent that uses external tools through MCP, delegates to subagents and runs unattended under explicit rules.
Common questions
Does Aider support MCP?
Aider's documentation does not describe MCP support as of September 2026. OHarness has a built-in MCP client for stdio and Streamable HTTP servers.
Does OHarness commit changes to git like Aider?
OHarness edits files and runs git through its tools when asked, under your permission rules, but it does not auto-commit every change the way Aider does. Aider's git-first workflow is one of its genuine strengths.
Can both run with local models?
Yes. Aider supports Ollama and OpenAI-compatible local servers; OHarness has Ollama, LM Studio and vLLM as built-in providers.
Sources
Spotted something out of date? Tell us and it will be corrected. More comparisons are on the guides page, and Claude Code alternatives covers what to check before switching.