clank.nvim

clank.nvim wires AI coding "harnesses" (Claude Code and opencode, with more planned) into Neovim through a small provider abstraction, so you can send a visual selection to the model and have the result applied directly to your buffer (reversible with normal u undo).

Requirements

• Neovim >= 0.10
• The claude CLI on your $PATH (for the default claude harness), or the opencode CLI (for the opencode harness)

Installation

With vim.pack (Neovim >= 0.12):

vim.pack.add({
  "https://github.com/bxrne/clank.nvim",
})

require("clank").setup()

With lazy.nvim:

{
  "bxrne/clank.nvim",
  opts = {},
}

Setup

require("clank").setup({
  harness = "claude",   -- which provider to dispatch to
  model = "sonnet-4.6",
  keymaps = {
    fill = "<leader>af", -- visual-mode keymap, set to false to disable
  },
})

Commands

:ClankFill

Send the current visual selection to the configured harness, asking it to fill in / complete the selected code, and replace the selection with the response. Also bound to the keymaps.fill keymap (default <leader>af) in visual mode.

Usage: select a block (e.g. an empty function body) in visual mode, then press <leader>af (or run :ClankFill).

:ClankReview {n}

Send a git diff to the configured harness for review and load its comments into the quickfix list. Requires git to be on $PATH and the current working directory to be inside a git repository.

The required integer argument selects what to review:

• 0 — uncommitted changes (staged and unstaged)
• 1 — the most recent commit
• 2 — the commit before that
• ...and so on

The harness is asked to respond with one path:line: message line per issue, which is parsed straight into the quickfix list (:copen to view).

Usage: :ClankReview 0 to review your working tree changes, :ClankReview 1 to review the last commit, etc.

:ClankFix

Send the buffers referenced by the quickfix list to the configured harness, asking it to fix the listed issues, and replace each buffer's contents with the response.

Run :ClankFix with no range to fix every entry in the quickfix list. Alternatively, from the quickfix window (:copen), select a range of lines in visual mode and run :'<,'>ClankFix to fix only those entries.

:ClankDo {prompt}

Give the configured harness a free-form task in natural language. The harness explores the repository as needed and responds with a structured plan of Neovim actions, which clank then executes for you. Because the default claude harness is agentic, it can read files and run git while deciding what to do.

:ClankDo review all the hotspots and add them to my quickfix list
:ClankDo rename the Config type to ClankConfig everywhere
:ClankDo open a vertical split with the busiest source file

The harness must reply with a JSON object, { "actions": [ ... ] }, where each action is one of:

• { "type": "command", "command": "<ex command>" } — run an Ex command (e.g. copen, vsplit foo.lua).
• { "type": "qflist", "action": "r"|"a", "items": [...] } — replace (r) or append (a) quickfix items ({ filename, lnum, text }).
• { "type": "edit", "path": "<path>", "content": "<full new contents>" } — overwrite a file's buffer with new contents (reversible with u).

Before anything runs, clank shows the plan and asks for confirmation. Set agent.confirm = false to apply plans without prompting.

Configuration

Option	Type	Default	Description
harness	string	"claude"	Provider used to handle requests
model	string	"sonnet-4.6"	Model passed to the harness
keymaps.fill	string|false	"<leader>af"	Visual-mode keymap for :ClankFill, false to disable
agent.confirm	boolean	true	Confirm before running a :ClankDo action plan

Providers

Providers are registered against lua/clank/provider/init.lua's registry and implement a send(opts, callbacks) contract:

-- opts: { prompt, system?, session_id?, cwd }
-- callbacks: { on_chunk(text), on_done(result), on_error(err) }
-- returns a handle with handle.cancel()

The built-in claude provider shells out to the claude CLI in headless mode (claude -p ... --output-format text). The built-in opencode provider shells out to opencode run ...; its models are addressed as provider/model (e.g. anthropic/claude-sonnet-4-5), and any provider/model string is accepted. Additional harnesses (Codex, etc.) can be added by implementing the same contract and registering under a new name.

To use opencode:

require("clank").setup({
  harness = "opencode",
  model = "anthropic/claude-sonnet-4-5",
})

Development

make test

Tests run via plenary.nvim + busted. The claude provider's tests stub vim.system, so no real CLI invocation or network access is required.