promptline.nvim

AI-powered inline text editor for Neovim. Select code or text in visual mode, describe what you want, and the selection is replaced in-place. Press u to undo.

Screenshots

Quickly get local explanation from any window, even claude

Features

• Visual mode selection → float prompt → in-place replacement
• Native undo (u) — replacement is a single undo step
• LSP diagnostics automatically included in the prompt (no need to describe the error)
• LSP formatting applied after replacement, file saved automatically
• Preset mode selector with <C-n>/<C-p> — opens a side picker, <Enter> uses the selected mode's default prompt or whatever you typed
• Explain mode — shows the AI response in the float without touching your buffer
• Three backends: Claude CLI, Anthropic API, CopilotChat

Requirements

• Neovim 0.9+
• One of:
  • claude CLI installed and logged in (claude_cli backend)
  • ANTHROPIC_API_KEY env var + curl (anthropic_api backend)
  • CopilotChat.nvim installed (copilot_chat backend)

Installation

lazy.nvim

{
  "igorgn/promptline.nvim",
  config = function()
    require("promptline").setup()
  end,
}

Local path (development)

{
  dir = "/path/to/promptline.nvim",
  config = function()
    require("promptline").setup()
  end,
}

Usage

1. Select text in Visual mode
2. Press <leader>p (default keymap)
3. A float prompt appears:
   • Type a custom instruction and press <Enter>
   • Or press <C-n>/<C-p> to open the mode picker — a small window appears showing available presets, cycling highlights the active one
   • <Enter> with empty input uses the selected preset's default prompt
   • <Esc> or focusing another window cancels
4. A spinner shows in the float while the AI is working
5. Edit mode: selection replaced in-place, LSP formatting applied, file saved
6. Explain mode: result shown in the float — press q or <Esc> to close
7. Press u to undo any edit

Default Presets

Label	Default prompt	Mode
Fix	Fix the issues in this code	edit
Improve	Improve this	edit
Explain	Explain what this code does clearly	explain

Presets are fully customizable — see Configuration below.

Configuration

All options with their defaults:

require("promptline").setup({
  -- Backend to use for AI requests
  -- "claude_cli"    — uses the `claude` binary (existing Claude Code login, no API key needed)
  -- "anthropic_api" — calls the Anthropic REST API directly
  -- "copilot_chat"  — uses CopilotChat.nvim (requires the plugin to be installed)
  backend = "claude_cli",

  -- Model for the anthropic_api backend
  model = "claude-haiku-4-5",
  max_tokens = 8096,

  -- API key for anthropic_api backend (falls back to $ANTHROPIC_API_KEY env var)
  api_key = nil,

  -- Used when submitting with empty input and no preset selected
  default_prompt = "Improve this",

  -- System prompt for edit mode
  system_prompt = "You are a precise code and text editor. When given text and an instruction, you apply the instruction and return only the edited result.",

  -- Visual mode keymap that triggers the plugin
  keymap = "<leader>p",

  -- Width of the prompt float window
  float_width = 60,

  -- Run LSP formatter on the buffer after applying a change
  format_on_apply = true,

  -- Presets cycled with <C-n>/<C-p> in the prompt window.
  -- Selecting a preset sets the active mode; empty input uses its default prompt.
  -- Typing your own input overrides the preset prompt but keeps the mode.
  -- mode = "edit"    — replaces the selection with the AI response
  -- mode = "explain" — shows the AI response in the float without editing the buffer
  presets = {
    { label = "Fix",     prompt = "Fix the issues in this code",        mode = "edit" },
    { label = "Improve", prompt = "Improve this",                       mode = "edit" },
    { label = "Explain", prompt = "Explain what this code does clearly", mode = "explain" },
  },
})

Examples

Selection	Input	Result
Rust function with type error	Fix preset (LSP error auto-included)	Fixes the type error
Any code	Make more idiomatic	Rewrites using idiomatic patterns
Long function	Split into smaller functions	Refactors in-place
Paragraph	Make concise	Shortens while preserving meaning
Code block	Explain preset	Explanation shown in float, buffer untouched

Backends

claude_cli (default)

Uses your existing Claude Code login — no API key required.

require("promptline").setup({
  backend = "claude_cli",
})

Requires the claude CLI to be installed and authenticated (claude auth login).

anthropic_api

Calls the Anthropic API directly using curl.

require("promptline").setup({
  backend = "anthropic_api",
  model = "claude-sonnet-4-6",  -- or any Claude model
  -- api_key = "sk-ant-...",    -- or set ANTHROPIC_API_KEY env var
})

copilot_chat

Uses CopilotChat.nvim — fast, uses your existing GitHub Copilot subscription.

require("promptline").setup({
  backend = "copilot_chat",
})

Requires CopilotChat.nvim to be installed.