neovim-use-mcp

An MCP server that edits files through a real Neovim instance. Your agent gets your language servers, your formatters and your plugins, not a plain text writer.

• Real LSP — diagnostics after every edit, rename, code actions, hover, references, document and workspace symbols.
• Minimal diffs — edit tools save the buffer with noautocmd write by default, so BufWritePre (format-on-save) does not run. Only the edited lines change. Use nvim_format to format explicitly.
• Plugin access — nvim_command and nvim_exec_lua reach anything else.
• stdio transport — the server starts with the agent and stops with it. It also stops the Neovim child process.

Requirements

| Item | Version | Note | |---|---|---| | Node.js | 18 or later | The server runs on Node. | | Neovim | 0.10 or later | The server calls vim.lsp.get_clients. | | A Neovim config | optional | Without one, you get edits but no LSP. |

Check your Neovim first:

nvim --version
nvim --headless --embed   # must start and stay quiet; press Ctrl-C to stop

If that command prints errors, a plugin breaks headless start. Use --config-mode minimal until you fix the plugin.

Install

From npm (recommended)

npm install -g neovim-use-mcp

Or use npx without a global install:

npx neovim-use-mcp

From source

git clone https://github.com/santanusinha/neovim-use-mcp.git
cd neovim-use-mcp
npm install
npm run build

The build writes dist/index.js. That file is the server.

Connect an agent

Add the server to your MCP client config.

With npx (no install needed):

{
  "mcpServers": {
    "neovim": {
      "command": "npx",
      "args": ["neovim-use-mcp"],
      "env": {
        "NVIM_MCP_CWD": "/absolute/path/to/your/project"
      }
    }
  }
}

With a global install:

{
  "mcpServers": {
    "neovim": {
      "command": "neovim-use-mcp",
      "env": {
        "NVIM_MCP_CWD": "/absolute/path/to/your/project"
      }
    }
  }
}

From a local build:

{
  "mcpServers": {
    "neovim": {
      "command": "node",
      "args": ["/absolute/path/to/neovim-use-mcp/dist/index.js"],
      "env": {
        "NVIM_MCP_CWD": "/absolute/path/to/your/project"
      }
    }
  }
}

[!TIP] NVIM_MCP_CWD sets the project root. The language server uses that root to find tsconfig.json, go.mod, Cargo.toml and so on. If you leave it out, the server uses the directory that the agent starts it in.

The server needs no start or stop command. The agent starts it over stdio and stops it on exit. The server then stops its Neovim child process.

First run

Ask your agent to open a file:

Open src/util/format.ts with the Neovim tools.

A correct answer looks like this:

Opened src/util/format.ts (buffer 1, 59 lines, filetype typescript).
LSP clients: null-ls, quick_lint_js, ts_ls

If you see No LSP client attached, read When no LSP attaches.

How an agent should work

The tools follow one simple order.

1. Open the file(s) with nvim_open_file. Pass an array of paths to open several files at once. This starts the language server. Every LSP tool needs an open buffer.
2. Read with nvim_read_file to get numbered lines.
3. Edit with nvim_edit_text, nvim_edit_lines or nvim_insert_lines. Each edit saves the file and returns fresh diagnostics.
4. Fix any new diagnostic with nvim_code_actions.

Three rules make the results much better:

• Use nvim_rename_symbol for a rename. Do not use a text replace. The LSP changes every file, and a text replace does not.
• Use nvim_edit_text when you know the exact text. It fails if the text is not unique, which stops a wrong edit.
• Stage a multi-file change with save: false, then call nvim_save_buffer once per file.

Tools

The server loads one of two tiers. The --tools flag picks the tier. minimal is the default and loads the 10 tools an agent runs all day. full loads all 18 tools. No tool is deleted; the tier only decides what loads into the agent's context.

Minimal tier (default, 10 tools)

| Tool | Arguments | Purpose | |---|---|---| | nvim_open_file | path (string or array), wait_ms? | Pre-warm files or tune the LSP wait. Other tools open files on demand | | nvim_read_file | path, start_line?, end_line? | Read numbered lines | | nvim_edit_lines | path, start_line, end_line, text, save? | Replace a range, or insert before a line with start_line = end_line + 1. The default edit tool | | nvim_format | path, start_line?, end_line? | Format a file or a range | | nvim_rename_symbol | path, line, column, new_name | Rename across the workspace | | nvim_goto_definition | path, line, column, wait_ms? | Find a definition | | nvim_references | path, line, column, wait_ms? | Find every reference | | nvim_hover | path, line, column, wait_ms? | Type and documentation | | nvim_code_actions | path, line, column, apply_index? | List or apply a quick fix | | nvim_exec_lua | code, args? | Run Lua inside Neovim |

Full tier adds (8 tools)

| Tool | Arguments | Purpose | |---|---|---| | nvim_edit_text | path, old_text, new_text, replace_all?, save? | Replace exact text. Tolerates whitespace drift and preserves indentation | | nvim_insert_lines | path, line, text, save? | Insert text before a line. Prefer nvim_edit_lines insert mode | | nvim_save_buffer | path | Write a buffer (no format-on-save autocmds) | | nvim_diagnostics | path?, severity?, wait_ms? | Errors and warnings for one file or all buffers | | nvim_list_buffers | — | List open buffers | | nvim_document_symbols | path, wait_ms? | Outline a file | | nvim_workspace_symbols | query, path?, wait_ms? | Search symbols in the project | | nvim_command | command | Run an Ex command, for example a plugin command |

Lines and columns start at 1.

Edit tools save the buffer by default and return fresh diagnostics, both as text and as a structured payload: { saved, line_count, errors, warnings, infos, diagnostics[] }.

nvim_exec_lua runs any code. Turn it off with --no-exec if the agent is not trusted. not trusted.

Recipes

Fix every error in a file

nvim_open_file    path=src/app.ts
nvim_diagnostics  path=src/app.ts severity=error
nvim_code_actions path=src/app.ts line=42 column=9        # list
nvim_code_actions path=src/app.ts line=42 column=9 apply_index=1

Rename a symbol everywhere

nvim_open_file      path=src/util/format.ts
nvim_document_symbols path=src/util/format.ts             # find the line
nvim_rename_symbol  path=src/util/format.ts line=28 column=17 new_name=renderIssues

The tool returns the list of files that it changed and saved.

Change several places, then save once

nvim_edit_text path=src/a.ts old_text="foo(" new_text="bar(" save=false
nvim_edit_text path=src/a.ts old_text="= foo" new_text="= bar" save=false
nvim_save_buffer path=src/a.ts

Run a plugin command

nvim_command command="Telescope find_files"
nvim_exec_lua code="return vim.fn.getcwd()"

Options

Command line flags win over environment variables.

| Flag | Environment | Default | Meaning | |---|---|---|---| | --mode | NVIM_MCP_MODE | embedded | embedded spawns its own nvim; attach connects to a socket | | --socket | NVIM_MCP_SOCKET | — | Socket for attach mode | | --nvim | NVIM_MCP_BIN | nvim | Path to the nvim binary | | --config-mode | NVIM_MCP_CONFIG_MODE | user | user loads your config; minimal runs nvim --clean | | --no-exec | NVIM_MCP_ALLOW_EXEC=0 | exec on | Turn off nvim_exec_lua and nvim_command | | --tools | NVIM_MCP_TOOLS | minimal | minimal loads 10 tools; full loads all 18 | | --cwd | NVIM_MCP_CWD | process cwd | Project root for the LSP | | --lsp-wait-ms | NVIM_MCP_LSP_WAIT_MS | 3000 | Default LSP wait | | --diag-wait-ms | NVIM_MCP_DIAG_WAIT_MS | 500 | Diagnostics settle wait after an edit; floor 250 | | --debug | NVIM_MCP_DEBUG | off | Debug lines on stderr |

Watch the agent work

Attach mode shows you every edit in your own window, live.

Recipes

Fix every error in a file

nvim_read_file    path=src/app.ts                          # implicit open
nvim_edit_lines   path=src/app.ts start_line=42 end_line=42 text="..."
                                                            # feedback carries diagnostics
nvim_code_actions path=src/app.ts line=42 column=9 apply_index=1

Rename a symbol everywhere

nvim_rename_symbol  path=src/util/format.ts line=28 column=17 new_name=renderIssues

The tool returns the list of files that it changed and saved.

Insert before a line

nvim_edit_lines path=src/app.ts start_line=5 end_line=4 text="import { join } from \"node:path\";"

start_line = end_line + 1 means insert before start_line.

Stage several edits, then save once (full tier)

nvim_edit_lines  path=src/a.ts start_line=10 end_line=10 text="..." save=false
nvim_edit_lines  path=src/a.ts start_line=20 end_line=20 text="..." save=false
nvim_save_buffer path=src/a.ts

Run a plugin command (full tier)

nvim_command command="Telescope find_files"
nvim_exec_lua code="return vim.fn.getcwd()"

A tool is missing

The minimal tier loads 10 tools. Start the server with --tools full to load all 18. Full-tier tool descriptions start with "Full-tier tool".

A language server does not attach

1. Check that the file type has a language server in your Neovim config.
2. Call nvim_open_file with a longer wait_ms, for example 10000.
3. Confirm the server starts in your own Neovim for the same file.

A stale swap file blocks or warns

The server never writes swap files and never stops on the E325 prompt. A swap file that sits next to a target file is stale, or another editor owns it. nvim_open_file still opens the file and prints a note:

Stale swap file ignored: /path/.file.txt.swp. Delete it to remove this note.

Delete the .swp file to remove the note. The structured result carries the path in stale_swap.

The server does not start

Run it by hand and read stderr:

NVIM_MCP_DEBUG=1 node dist/index.js

A healthy start prints:

[nvim-mcp] ready (mode=embedded, tools=minimal, exec=true, cwd=/your/project)

A plugin breaks headless Neovim

Use --config-mode minimal. The server then runs nvim --clean. You keep the edit tools, but you lose your plugins and your LSP setup.

Diagnostics look wrong or stale

A linter bridge, for example null-ls with eslint_d, reports an error when the project has no lint config. Add the config, or make the null-ls source conditional on a config file. This is an editor setup problem, not a server problem.

A tool says the text is not unique

nvim_edit_text refuses an ambiguous match on purpose. Add more context lines to old_text, or set replace_all: true if you truly want every match.

Development

npm run dev              # tsc --watch
npm test                 # vitest, uses a real headless nvim
npm run typecheck        # tsc --noEmit
npm run inspect          # MCP Inspector UI

Docker

A Dockerfile is included for isolated or CI usage. The image bundles Node and Neovim, but has no user Neovim config. Mount your config if you need LSP:

docker build -t neovim-use-mcp .
docker run --rm neovim-use-mcp

Releasing

Releases publish to npm through GitHub Actions with OIDC trusted publishing. No npm token is stored.

1. Bump the version in package.json.
2. Tag and push: git tag v0.x.0 && git push origin v0.x.0.
3. Create a GitHub Release from the tag.
4. The Publish to npm workflow builds, tests, and publishes automatically.

Licence

MIT

[!CAUTION] This is completely vibe coded. I guarantee absolutely nothing!!