Long-horizon coding tasks, done in the terminal

Plandex is an MIT-licensed AI coding agent that runs in your terminal and specializes in long, multi-file tasks — refactors, migrations, feature implementation. Where most coding AIs jump straight to a diff, Plandex builds an explicit plan first, lets you review and revise it, then executes step-by-step with automatic sandboxing and version control. You bring your own API keys (OpenAI, Anthropic, Google, OpenRouter) so you only pay for what you use.

Who it's for: Backend/full-stack engineers, solo founders, and open-source maintainers who prefer the terminal, want to control costs via BYOK, and tackle tasks too large for a single inline diff.

Key features

Plan Plan-first workflow

Plandex drafts an explicit task plan before touching code. You edit, reject, or approve steps before execution — no more surprise 30-file diffs that you have to undo.

Sandbox Sandboxed execution

Changes are applied to an isolated branch by default. See a diff, run tests, and only commit when you're satisfied. Bad states are one command to rewind.

BYOK Bring your own keys

Plug in OpenAI, Anthropic, Google, or OpenRouter API keys. No per-seat SaaS pricing — you pay the model provider directly, which is dramatically cheaper for power users.

Terminal Native terminal UX

Single binary install, works over SSH, in Docker, in CI. Pairs naturally with tmux, vim, and any editor you already use — no IDE lock-in.

The honest take

✓ What works

Plan-first model is genuinely safer for large refactors than fire-and-forget agents
BYOK pricing means heavy users pay a fraction of Cursor/Windsurf subscriptions
Sandboxed branches + rewind removes the fear of letting an agent loose on a real repo
Open source (MIT) — self-host, audit, or fork freely
Works great over SSH for remote/headless dev boxes

✗ What doesn't

No inline IDE experience — you live in the terminal
Setup requires comfort with API keys and CLIs (not for casual users)
No built-in tab completion — pair it with Copilot/Continue for inline autocomplete
Smaller community than Aider; fewer plugins and integrations

Verdict

Plandex fills the gap between "Copilot-style autocomplete" and "agentic IDE" — it's the right tool when a task is too big for a single diff but you still want to stay in your terminal and your own editor. Pair it with a free completion tool and a $5 API credit, and you've got a serious Cursor alternative for under $10/mo.

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