tmux-sendit.nvim

Send selected buffer contents, file paths, or diagnostics to another tmux pane without leaving neovim.

Select code, a file path, or diagnostics, pick a target pane, and the content is inserted as if you typed it. Useful for feeding code snippets, file references, diagnostics, or context to a CLI tool running in another pane - like sending selections to a claude code session without constantly switching between tmux panes.

Requirements

• neovim >= 0.9
• tmux

Installation

lazy.nvim

{
  "js/tmux-sendit.nvim",
  opts = {},
}

packer.nvim

use {
  "js/tmux-sendit.nvim",
  config = function()
    require("sendit").setup({})
  end,
}

mini.deps

MiniDeps.add({
  source = "js/tmux-sendit.nvim",
})
require("sendit").setup({})

Configuration

These are the defaults — pass any overrides to setup():

require("sendit").setup({
  -- shell command used to send text to a tmux pane
  cmd = { "tmux", "send-keys", "-t" },

  -- scope for listing tmux panes: "window", "session", or "all"
  pane_scope = "session",

  -- focus the destination pane after sending
  focus_after_send = true,

  -- remember and reuse last used pane, will always send to this pane until `:Sendit reset`
  remember_last = true,

  -- prefix/suffix wrapped around selections sent to the pane
  selection_prefix = "\n```",
  selection_suffix = "```\n",

  -- prefix/suffix wrapped around file paths sent to the pane
  path_prefix = "@",
  path_suffix = " ",

  -- format for line range appended to paths in visual mode
  path_range_format = "#L{start}-L{end}",

  -- function returning the pane list for the picker, or nil to show every pane in scope.
  -- The default restricts the picker to panes running known coding-agent processes
  -- (claude, codex, opencode, gemini, copilot, pi).
  process_filter = function()
    return require("sendit.processes").filter({
      "claude", "codex", "opencode", "gemini", "copilot", "pi",
    })
  end,
})

Filtering the pane picker

By default the picker only lists tmux panes whose process tree contains a known coding-agent CLI. The list is matched against a small built-in registry that walks each pane's process descendants (so node/python-wrapped CLIs like claude or codex are detected even when the foreground process reports as node). Built-in names: claude, codex, opencode, gemini, copilot (excluding copilot-language-server), and pi.

To narrow or extend the set, pass a different name list:

process_filter = function()
  return require("sendit.sessions").filter({ "claude", "codex" })
end,

To disable filtering entirely and show every pane in scope:

process_filter = nil,

For fully custom logic, supply your own function returning a list of pane tables ({ tmux_id, id, command, agent? }).

Commands & Keybindings

No keybindings are set by default. Bind the functions you need in your config:

-- lazy.nvim example with keybindings
{
  "js/tmux-sendit.nvim",
  keys = {
    { "<leader>a", group = "sendit", icon = "", desc = "sendit to tmux" },
    { "<leader>as", function() require("sendit").send_selection() end, mode = "v", desc = "Send selection to tmux pane" },
    { "<leader>af", function() require("sendit").send_rel_path() end, mode = { "n", "v" }, desc = "Send relative file path to tmux pane" },
    { "<leader>aF", function() require("sendit").send_abs_path() end, mode = { "n", "v" }, desc = "Send absolute file path to tmux pane" },
    { "<leader>ad", function() require("sendit").send_diagnostic() end, mode = { "n", "v" }, desc = "Send diagnostics to tmux pane" },
  },
  opts = {},
}

Commands

command / key	mode	description
:Sendit selection	visual	send the current visual selection
:Sendit path	n / v	send the project-relative file path (with line range in visual mode)
:Sendit fullpath	n / v	send the absolute file path (with line range in visual mode)
:Sendit diagnostic	normal	send diagnostics to tmux pane
:Sendit reset	normal	clear the remembered target pane

Pane Selection

The pane picker automatically filters out the pane running neovim. When only one target pane is available, it sends directly without prompting. After selecting a pane, it's remembered for subsequent sends — use :Sendit reset to clear it.

License

MIT