sidekick

Sidekick

You still write code by hand. So does Claude Code.

Same files, same time, nobody typing over anybody. Sidekick keeps Neovim and your agents — Codex, opencode, pi, Crush, Amp, Antigravity, Grok — out of each other's way.

                                                              

A conduit between Neovim and your AI agents — so they wait when you're typing.

Skip to 1:20 to see a block. The same recording is bundled in the binary — run sidekick demo after install to play it back offline.

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I do less and less coding by hand. The part I still do, I do very deliberately — pop open a new pane, open Neovim, start editing. It's a flow state I have to push myself into. The catch: Neovim is the only thing in the system that knows I'm typing. When the agent in the next pane decides the file I'm in needs editing, the buffer reloads, my work gone. So I decided to do something about it.

Sidekick is the conduit between the editor and the agents. When you have unsaved changes in a buffer, the agents wait — the edit is denied, your buffer is untouched. Save the file and the next attempt proceeds. No flags, no confirmation prompts, no policy file. The 99% of edits that don't conflict with you go through untouched.

The other direction works too: when the AI modifies a file you have open, Sidekick refreshes the buffer in every Neovim instance, cursor position preserved.

What changes in your workflow

• The AI waits on a file while you're editing it. You'll see this in Neovim: Edit blocked — file has unsaved changes.
• A file the AI edits while you have it open is auto-reloaded — no :e! dance.
• A current or recent visual selection in Neovim can be added to your next Claude Code, Codex, opencode, or pi prompt as context. Select code, type the prompt, hit enter.

Everything else stays the same. You keep using nvim like normal.

Install

cargo install sidekick
sidekick init

sidekick init walks through every AI harness it finds on your machine, wires the hooks, sets up the nvim alias, and skips anything already done. Re-run any time — it's idempotent.

Verify with sidekick doctor. Want to wire things by hand? See docs/SETUP.md.

Harness support

Harness	Edit deny	Buffer refresh	Selection injection
Claude Code	✓	✓	✓
Codex	✓	✓	✓
opencode	✓	✓	✓
pi	✓	✓	✓
Crush	✓	—	—
Amp	✓	✓	—
Antigravity	✓	✓	—
Grok	✓	✓	—

A — is an upstream gap: the harness doesn't expose the hook event sidekick would need.

Usage

Just use nvim. The shell alias routes through sidekick so the hook can find your editor.

nvim src/main.rs

If you do not want the alias, run sidekick neovim <args> directly. You won't notice anything different until an agent tries to overwrite unsaved work, at which point sidekick denies the edit and tells the agent why.