Plandex

Open SourceMIT / AGPL-3.0Self-hostable

The terminal AI coding agent built for large, real-world tasks — a 2M-token effective context and a sandbox where you review every diff before it lands. A powerful Claude Code alternative.

Open source alternative to

Claude Code

Visit Plandex View source

About Plandex

Plandex is a terminal-based AI coding agent designed for big tasks — the kind that span many files and would blow past a normal context window. It manages an effective context up to around 2M tokens and keeps your changes in a protected sandbox, so nothing touches your project files until you approve it.

That review-first design is its signature: you can let the agent plan and generate extensive changes, then step through diffs and apply exactly what you want. You bring your own model and can self-host the whole thing, including the server and database.

It's licensed under MIT and AGPL (open-source server), with a focused, active community. For developers tackling large, multi-file changes who want an agent with serious context and careful, reviewable output, Plandex is a standout open alternative to Claude Code.

Key features

Huge effective context — Manages up to roughly 2M tokens of context, built for large, multi-file tasks.
Diff-review sandbox — Changes stay in a protected sandbox until you review each diff and choose to apply it.
Terminal-native agent — Plans and generates extensive changes from the command line, with clear controls.
Bring your own model — Connect your own provider or model and self-host the server and database.

The honest read

What we like

Built for large, multi-file tasks with big context
Review-first sandbox keeps your project safe
Fully self-hostable, including server and DB
Open source (MIT / AGPL)
Terminal-native and scriptable

Worth knowing

Self-hosting the server and Postgres takes setup
Big-context runs on premium models can cost more
Terminal-only workflow isn't for everyone
Smaller community than the biggest agents

FAQ

Is Plandex free to use?

Yes — Plandex is open source (MIT and AGPL). You pay for the model you connect and, if self-hosting, your own server.

How is Plandex different from Claude Code?

Plandex is open source, self-hostable and built around a huge context and a review-first sandbox for large tasks, while Claude Code is tied to Anthropic's platform.

How big is Plandex's context?

It manages an effective context up to roughly 2 million tokens, making it suited to large, multi-file changes.

Does Plandex apply changes automatically?

No — changes are held in a sandbox so you review each diff before applying, keeping your project safe.

Can I self-host Plandex?

Yes — you can self-host the full stack, including the server and PostgreSQL database, and bring your own model.