Plandex is an open-source AI coding agent that runs directly in your terminal. It’s built for large codebases, big files, and multi-step engineering work that goes beyond simple one-off code generation.
Built for whole projects, not single files
Plandex uses context management with up to 2M tokens, helping the agent keep more of your project in view at once. This makes it easier to:
- Update modules without losing cross-file consistency
- Refactor larger areas of a codebase
- Add features that touch multiple parts of a project
Autonomy controls and workflows
You can choose how hands-on you want to be:
- Auto mode: the agent goes from task analysis to code changes on its own
- Step-by-step mode: the agent proposes changes and explains each step for review
Diff sandbox for safer changes
Edits go through a sandbox with diff-based review, which supports safer iteration:
- Review changes before applying them
- Roll back unsuccessful edits quickly
- Move toward production-ready updates with more control
As an open-source tool, Plandex fits into a developer’s existing terminal workflow.

