Copilot Chat for Neovim

cchat.mp4

Requirements

• Neovim 0.9.5+ - Older versions are not supported, and for best compatibility 0.10.0+ is preferred
• curl - 8.0.0+ is recommended for best compatibility. Should be installed by default on most systems and also shipped with Neovim
• Copilot chat in the IDE setting enabled in GitHub settings
• (Optional) tiktoken_core - Used for more accurate token counting
  • For Arch Linux users, you can install luajit-tiktoken-bin or lua51-tiktoken-bin from aur
  • Alternatively, install via luarocks: sudo luarocks install --lua-version 5.1 tiktoken_core
  • Alternatively, download a pre-built binary from lua-tiktoken releases. You can check your Lua PATH in Neovim by doing :lua print(package.cpath). Save the binary as tiktoken_core.so in any of the given paths.
• (Optional) git - Used for fetching git diffs for git context
  • For Arch Linux users, you can install git from the official repositories
  • For other systems, use your package manager to install git. For windows use the installer provided from git site
• (Optional) lynx - Used for improved fetching of URLs for url context
  • For Arch Linux users, you can install lynx from the official repositories
  • For other systems, use your package manager to install lynx. For windows use the installer provided from lynx site

Warning

If you are on neovim < 0.11.0, you also might want to add noinsert and popup to your completeopt to make the chat completion behave well.

Installation

Lazy.nvim

return {
  {
    "CopilotC-Nvim/CopilotChat.nvim",
    dependencies = {
      { "github/copilot.vim" }, -- or zbirenbaum/copilot.lua
      { "nvim-lua/plenary.nvim", branch = "master" }, -- for curl, log and async functions
    },
    build = "make tiktoken", -- Only on MacOS or Linux
    opts = {
      -- See Configuration section for options
    },
    -- See Commands section for default commands if you want to lazy load on them
  },
}

See @jellydn for configuration

Vim-Plug

Similar to the lazy setup, you can use the following configuration:

call plug#begin()
Plug 'github/copilot.vim'
Plug 'nvim-lua/plenary.nvim'
Plug 'CopilotC-Nvim/CopilotChat.nvim'
call plug#end()

lua << EOF
require("CopilotChat").setup {
  -- See Configuration section for options
}
EOF

Manual

1. Put the files in the right place

mkdir -p ~/.config/nvim/pack/copilotchat/start
cd ~/.config/nvim/pack/copilotchat/start

git clone https://github.com/github/copilot.vim
git clone https://github.com/nvim-lua/plenary.nvim

git clone https://github.com/CopilotC-Nvim/CopilotChat.nvim

2. Add to your configuration (e.g. ~/.config/nvim/init.lua)

require("CopilotChat").setup {
  -- See Configuration section for options
}

See @deathbeam for configuration

Usage

Commands

• :CopilotChat <input>? - Open chat window with optional input
• :CopilotChatOpen - Open chat window
• :CopilotChatClose - Close chat window
• :CopilotChatToggle - Toggle chat window
• :CopilotChatStop - Stop current copilot output
• :CopilotChatReset - Reset chat window
• :CopilotChatSave <name>? - Save chat history to file
• :CopilotChatLoad <name>? - Load chat history from file
• :CopilotChatDebugInfo - Show debug information
• :CopilotChatModels - View and select available models. This is reset when a new instance is made. Please set your model in init.lua for persistence.
• :CopilotChatAgents - View and select available agents. This is reset when a new instance is made. Please set your agent in init.lua for persistence.
• :CopilotChat<PromptName> - Ask a question with a specific prompt. For example, :CopilotChatExplain will ask a question with the Explain prompt. See Prompts for more information.

Chat Mappings

• <Tab> - Trigger completion menu for special tokens or accept current completion (see help)
• q/<C-c> - Close the chat window
• <C-l> - Reset and clear the chat window
• <CR>/<C-s> - Submit the current prompt
• gr - Toggle sticky prompt for the line under cursor
• <C-y> - Accept nearest diff (works best with COPILOT_GENERATE prompt)
• gj - Jump to section of nearest diff. If in different buffer, jumps there; creates buffer if needed (works best with COPILOT_GENERATE prompt)
• gq - Add all diffs from chat to quickfix list
• gy - Yank nearest diff to register (defaults to ")
• gd - Show diff between source and nearest diff
• gi - Show info about current chat (model, agent, system prompt)
• gc - Show current chat context
• gh - Show help message

The mappings can be customized by setting the mappings table in your configuration. Each mapping can have:

• normal: Key for normal mode
• insert: Key for insert mode
• detail: Description of what the mapping does

For example, to change the submit prompt mapping:

{
    mappings = {
      submit_prompt = {
        normal = '<Leader>s',
        insert = '<C-s>'
      }
    }
}

Prompts

You can ask Copilot to do various tasks with prompts. You can reference prompts with /PromptName in chat or call with command :CopilotChat<PromptName>.
Default prompts are:

• Explain - Write an explanation for the selected code as paragraphs of text
• Review - Review the selected code
• Fix - There is a problem in this code. Rewrite the code to show it with the bug fixed
• Optimize - Optimize the selected code to improve performance and readability
• Docs - Please add documentation comments to the selected code
• Tests - Please generate tests for my code
• Commit - Write commit message for the change with commitizen convention

You can define custom prompts like this (only prompt is required):

{
  prompts = {
    MyCustomPrompt = {
      prompt = 'Explain how it works.',
      system_prompt = 'You are very good at explaining stuff',
      mapping = '<leader>ccmc',
      description = 'My custom prompt description',
    }
  }
}

System Prompts

System prompts specify the behavior of the AI model. You can reference system prompts with /PROMPT_NAME in chat. Default system prompts are:

• COPILOT_INSTRUCTIONS - Base GitHub Copilot instructions
• COPILOT_EXPLAIN - On top of the base instructions adds coding tutor behavior
• COPILOT_REVIEW - On top of the base instructions adds code review behavior with instructions on how to generate diagnostics
• COPILOT_GENERATE - On top of the base instructions adds code generation behavior, with predefined formatting and generation rules

You can define custom system prompts like this (works same as prompts so you can combine prompt and system prompt definitions):

{
  prompts = {
    Yarrr = {
      system_prompt = 'You are fascinated by pirates, so please respond in pirate speak.',
    }
  }
}

Sticky Prompts

You can set sticky prompt in chat by prefixing the text with > using markdown blockquote syntax.
The sticky prompt will be copied at start of every new prompt in chat window. You can freely edit the sticky prompt, only rule is > prefix at beginning of line.
This is useful for preserving stuff like context and agent selection (see below).
Example usage:

> #files

List all files in the workspace

> @models Using Mistral-small

What is 1 + 11

Models

You can list available models with :CopilotChatModels command. Model determines the AI model used for the chat.
You can set the model in the prompt by using $ followed by the model name or default model via config using model key.
Default models are:

• gpt-4o - This is the default Copilot Chat model. It is a versatile, multimodal model that excels in both text and image processing and is designed to provide fast, reliable responses. It also has superior performance in non-English languages. Gpt-4o is hosted on Azure.
• claude-3.5-sonnet - This model excels at coding tasks across the entire software development lifecycle, from initial design to bug fixes, maintenance to optimizations. GitHub Copilot uses Claude 3.5 Sonnet hosted on Amazon Web Services. Claude is not available everywhere so if you do not see it, try github codespaces or VPN.
• o1-preview - This model is focused on advanced reasoning and solving complex problems, in particular in math and science. It responds more slowly than the gpt-4o model. You can make 10 requests to this model per day. o1-preview is hosted on Azure.
• o1-mini - This is the faster version of the o1-preview model, balancing the use of complex reasoning with the need for faster responses. It is best suited for code generation and small context operations. You can make 50 requests to this model per day. o1-mini is hosted on Azure.

For more information about models, see here
You can use more models from here by using @models agent from here (example: @models Using Mistral-small, what is 1 + 11)

Agents

Agents are used to determine the AI agent used for the chat. You can list available agents with :CopilotChatAgents command.
You can set the agent in the prompt by using @ followed by the agent name or default agent via config using agent key.
Default "noop" agent is copilot.

For more information about extension agents, see here
You can install more agents from here

Contexts

Contexts are used to determine the context of the chat.
You can add context to the prompt by using # followed by the context name or default context via config using context (can be single or array) key.
Any amount of context can be added to the prompt.
If context supports input, you can set the input in the prompt by using : followed by the input (or pressing complete key after :).
Default contexts are:

• buffer - Includes specified buffer in chat context. Supports input (default current).
• buffers - Includes all buffers in chat context. Supports input (default listed).
• file - Includes content of provided file in chat context. Supports input.
• files - Includes all non-hidden files in the current workspace in chat context. Supports input (default list).
  • files:list - Only lists file names.
  • files:full - Includes file content for each file found. Can be slow on large workspaces, use with care.
• git - Requires git. Includes current git diff in chat context. Supports input (default unstaged).
  • git:unstaged - Includes unstaged changes in chat context.
  • git:staged - Includes staged changes in chat context.
• url - Includes content of provided URL in chat context. Supports input.
• register - Includes contents of register in chat context. Supports input (default +, e.g clipboard).

You can define custom contexts like this:

{
  contexts = {
    birthday = {
      input = function(callback)
        vim.ui.select({ 'user', 'napoleon' }, {
          prompt = 'Select birthday> ',
        }, callback)
      end,
      resolve = function(input)
        input = input or 'user'
        local birthday = input
        if input == 'user' then
          birthday = birthday .. ' birthday is April 1, 1990'
        elseif input == 'napoleon' then
          birthday = birthday .. ' birthday is August 15, 1769'
        end

        return {
          {
            content = birthday,
            filename = input .. '_birthday',
            filetype = 'text',
          }
        }
      end
    }
  }
}

> #birthday:user

What is my birthday

Selections

Selections are used to determine the source of the chat (so basically what to chat about).
Selections are configurable either by default or by prompt.
Default selection is visual or buffer (if no visual selection).
Selection includes content, start and end position, buffer info and diagnostic info (if available). Supported selections that live in local select = require("CopilotChat.select") are:

• select.visual - Current visual selection.
• select.buffer - Current buffer content.
• select.line - Current line content.
• select.unnamed - Unnamed register content. This register contains last deleted, changed or yanked content.

You can chain multiple selections like this:

{
  selection = function(source)
    return select.visual(source) or select.buffer(source)
  end
}

API

local chat = require("CopilotChat")

-- Open chat window
chat.open()

-- Open chat window with custom options
chat.open({
  window = {
    layout = 'float',
    title = 'My Title',
  },
})

-- Close chat window
chat.close()

-- Toggle chat window
chat.toggle()

-- Toggle chat window with custom options
chat.toggle({
  window = {
    layout = 'float',
    title = 'My Title',
  },
})

-- Reset chat window
chat.reset()

-- Ask a question
chat.ask("Explain how it works.")

-- Ask a question with custom options
chat.ask("Explain how it works.", {
  selection = require("CopilotChat.select").buffer,
})

-- Ask a question and provide custom contexts
chat.ask("Explain how it works.", {
  context = { 'buffers', 'files', 'register:+' },
})

-- Ask a question and do something with the response
chat.ask("Show me something interesting", {
  callback = function(response)
    print("Response:", response)
  end,
})

-- Get all available prompts (can be used for integrations like fzf/telescope)
local prompts = chat.prompts()

-- Get last copilot response (also can be used for integrations and custom keymaps)
local response = chat.response()

-- Retrieve current chat config
local config = chat.config
print(config.model)

-- Pick a prompt using vim.ui.select
local actions = require("CopilotChat.actions")

-- Pick prompt actions
actions.pick(actions.prompt_actions({
    selection = require("CopilotChat.select").visual,
}))

-- Programmatically set log level
chat.log_level("debug")

Configuration

Default configuration

Also see here:

{

  -- Shared config starts here (can be passed to functions at runtime and configured via setup function)

  system_prompt = prompts.COPILOT_INSTRUCTIONS, -- System prompt to use (can be specified manually in prompt via /).
  model = 'gpt-4o', -- Default model to use, see ':CopilotChatModels' for available models (can be specified manually in prompt via $).
  agent = 'copilot', -- Default agent to use, see ':CopilotChatAgents' for available agents (can be specified manually in prompt via @).
  context = nil, -- Default context or array of contexts to use (can be specified manually in prompt via #).
  temperature = 0.1, -- GPT result temperature

  headless = false, -- Do not write to chat buffer and use history(useful for using callback for custom processing)
  callback = nil, -- Callback to use when ask response is received

  -- default selection
  selection = function(source)
    return select.visual(source) or select.buffer(source)
  end,

  -- default window options
  window = {
    layout = 'vertical', -- 'vertical', 'horizontal', 'float', 'replace'
    width = 0.5, -- fractional width of parent, or absolute width in columns when > 1
    height = 0.5, -- fractional height of parent, or absolute height in rows when > 1
    -- Options below only apply to floating windows
    relative = 'editor', -- 'editor', 'win', 'cursor', 'mouse'
    border = 'single', -- 'none', single', 'double', 'rounded', 'solid', 'shadow'
    row = nil, -- row position of the window, default is centered
    col = nil, -- column position of the window, default is centered
    title = 'Copilot Chat', -- title of chat window
    footer = nil, -- footer of chat window
    zindex = 1, -- determines if window is on top or below other floating windows
  },

  show_help = true, -- Shows help message as virtual lines when waiting for user input
  show_folds = true, -- Shows folds for sections in chat
  highlight_selection = true, -- Highlight selection
  highlight_headers = true, -- Highlight headers in chat, disable if using markdown renderers (like render-markdown.nvim)
  auto_follow_cursor = true, -- Auto-follow cursor in chat
  auto_insert_mode = false, -- Automatically enter insert mode when opening window and on new prompt
  insert_at_end = false, -- Move cursor to end of buffer when inserting text
  clear_chat_on_new_prompt = false, -- Clears chat on every new prompt

  -- Static config starts here (can be configured only via setup function)

  debug = false, -- Enable debug logging (same as 'log_level = 'debug')
  log_level = 'info', -- Log level to use, 'trace', 'debug', 'info', 'warn', 'error', 'fatal'
  proxy = nil, -- [protocol://]host[:port] Use this proxy
  allow_insecure = false, -- Allow insecure server connections

  chat_autocomplete = true, -- Enable chat autocompletion (when disabled, requires manual `mappings.complete` trigger)
  history_path = vim.fn.stdpath('data') .. '/copilotchat_history', -- Default path to stored history

  question_header = '# User ', -- Header to use for user questions
  answer_header = '# Copilot ', -- Header to use for AI answers
  error_header = '# Error ', -- Header to use for errors
  separator = '───', -- Separator to use in chat

  -- default contexts
  contexts = {
    buffer = {
      -- see config.lua for implementation
    },
    buffers = {
      -- see config.lua for implementation
    },
    file = {
      -- see config.lua for implementation
    },
    files = {
      -- see config.lua for implementation
    },
    git = {
      -- see config.lua for implementation
    },
    url = {
      -- see config.lua for implementation
    },
    register = {
      -- see config.lua for implementation
    },
  },

  -- default prompts
  prompts = {
    Explain = {
      prompt = '> /COPILOT_EXPLAIN\n\nWrite an explanation for the selected code as paragraphs of text.',
    },
    Review = {
      prompt = '> /COPILOT_REVIEW\n\nReview the selected code.',
      -- see config.lua for implementation
    },
    Fix = {
      prompt = '> /COPILOT_GENERATE\n\nThere is a problem in this code. Rewrite the code to show it with the bug fixed.',
    },
    Optimize = {
      prompt = '> /COPILOT_GENERATE\n\nOptimize the selected code to improve performance and readability.',
    },
    Docs = {
      prompt = '> /COPILOT_GENERATE\n\nPlease add documentation comments to the selected code.',
    },
    Tests = {
      prompt = '> /COPILOT_GENERATE\n\nPlease generate tests for my code.',
    },
    Commit = {
      prompt = '> #git:staged\n\nWrite commit message for the change with commitizen convention. Make sure the title has maximum 50 characters and message is wrapped at 72 characters. Wrap the whole message in code block with language gitcommit.',
    },
  },

  -- default mappings
  mappings = {
    complete = {
      insert = '<Tab>',
    },
    close = {
      normal = 'q',
      insert = '<C-c>',
    },
    reset = {
      normal = '<C-l>',
      insert = '<C-l>',
    },
    submit_prompt = {
      normal = '<CR>',
      insert = '<C-s>',
    },
    toggle_sticky = {
      detail = 'Makes line under cursor sticky or deletes sticky line.',
      normal = 'gr',
    },
    accept_diff = {
      normal = '<C-y>',
      insert = '<C-y>',
    },
    jump_to_diff = {
      normal = 'gj',
    },
    quickfix_diffs = {
      normal = 'gq',
    },
    yank_diff = {
      normal = 'gy',
      register = '"',
    },
    show_diff = {
      normal = 'gd',
    },
    show_info = {
      normal = 'gi',
    },
    show_context = {
      normal = 'gc',
    },
    show_help = {
      normal = 'gh',
    },
  },
}

Customizing buffers

You can set local options for the buffers that are created by this plugin, copilot-chat, copilot-diff, copilot-overlay:

vim.api.nvim_create_autocmd('BufEnter', {
    pattern = 'copilot-*',
    callback = function()
        vim.opt_local.relativenumber = true

        -- C-p to print last response
        vim.keymap.set('n', '<C-p>', function()
          print(require("CopilotChat").response())
        end, { buffer = true, remap = true })
    end
})

Tips

Quick chat with your buffer

To chat with Copilot using the entire content of the buffer, you can add the following configuration to your keymap:

-- lazy.nvim keys

  -- Quick chat with Copilot
  {
    "<leader>ccq",
    function()
      local input = vim.fn.input("Quick Chat: ")
      if input ~= "" then
        require("CopilotChat").ask(input, { selection = require("CopilotChat.select").buffer })
      end
    end,
    desc = "CopilotChat - Quick chat",
  }

Inline chat

Change the window layout to float and position relative to cursor to make the window look like inline chat. This will allow you to chat with Copilot without opening a new window.

-- lazy.nvim opts

  {
    window = {
      layout = 'float',
      relative = 'cursor',
      width = 1,
      height = 0.4,
      row = 1
    }
  }

Telescope integration

Requires telescope.nvim plugin to be installed.

-- lazy.nvim keys

  -- Show prompts actions with telescope
  {
    "<leader>ccp",
    function()
      local actions = require("CopilotChat.actions")
      require("CopilotChat.integrations.telescope").pick(actions.prompt_actions())
    end,
    desc = "CopilotChat - Prompt actions",
  },

fzf-lua integration

Requires fzf-lua plugin to be installed.

-- lazy.nvim keys

  -- Show prompts actions with fzf-lua
  {
    "<leader>ccp",
    function()
      local actions = require("CopilotChat.actions")
      require("CopilotChat.integrations.fzflua").pick(actions.prompt_actions())
    end,
    desc = "CopilotChat - Prompt actions",
  },

render-markdown integration

Requires render-markdown plugin to be installed.

-- Registers copilot-chat filetype for markdown rendering
require('render-markdown').setup({
  file_types = { 'markdown', 'copilot-chat' },
})

-- You might also want to disable default header highlighting for copilot chat when doing this and set error header style and separator
require('CopilotChat').setup({
  highlight_headers = false,
  separator = '---',
  error_header = '> [!ERROR] Error',
  -- rest of your config
})

Roadmap

• Improved caching for context (persistence through restarts/smarter caching)
• General QOL improvements

Development

Installing Pre-commit Tool

For development, you can use the provided Makefile command to install the pre-commit tool:

make install-pre-commit

This will install the pre-commit tool and the pre-commit hooks.

Contributors

If you want to contribute to this project, please read the CONTRIBUTING.md file.

Thanks goes to these wonderful people (emoji key):

gptlang 💻 📖	Dung Duc Huynh (Kaka) 💻 📖	Ahmed Haracic 💻	Trí Thiện Nguyễn 💻	He Zhizhou 💻	Guruprakash Rajakkannu 💻	kristofka 💻
PostCyberPunk 📖	Katsuhiko Nishimra 💻	Erno Hopearuoho 💻	Shaun Garwood 💻	neutrinoA4 💻 📖	Jack Muratore 💻	Adriel Velazquez 💻 📖
Tomas Slusny 💻 📖	Nisal 📖	Tobias Gårdhus 📖	Petr Dlouhý 📖	Dylan Madisetti 💻	Aaron Weisberg 💻 📖	Jose Tlacuilo 💻 📖
Kevin Traver 💻 📖	dTry 💻	Arata Furukawa 💻	Ling 💻	Ivan Frolov 💻	Folke Lemaitre 💻 📖	GitMurf 💻
Dmitrii Lipin 💻	jinzhongjia 📖	guill 💻	Sjon-Paul Brown 💻	Renzo Mondragón 💻 📖	fjchen7 💻	Radosław Woźniak 💻
JakubPecenka 💻	thomastthai 📖	Tomáš Janoušek 💻	Toddneal Stallworth 📖	Sergey Alexandrov 💻	Léopold Mebazaa 💻	JunKi Jin 💻
abdennourzahaf 📖

This project follows the all-contributors specification. Contributions of any kind are welcome!

Stargazers over time