#!/usr/bin/env node
import { Server } from "@modelcontextprotocol/sdk/server/index.js";
import { StdioServerTransport } from "@modelcontextprotocol/sdk/server/stdio.js";
import {
CallToolRequestSchema,
ListResourcesRequestSchema,
ListToolsRequestSchema,
ReadResourceRequestSchema,
} from "@modelcontextprotocol/sdk/types.js";
import {
getCurrentBuffer,
listOpenBuffers,
getBufferContent,
updateBuffer,
reloadBuffer,
reloadAllBuffers,
openFile,
} from "./lib/nvim-operations.js";
/**
* Create and start the MCP server
*/
async function main() {
const server = new Server(
{
name: "nvim-mcp-server",
version: "1.0.0",
},
{
capabilities: {
resources: {},
tools: {},
},
},
);
/**
* List available resources
*/
server.setRequestHandler(ListResourcesRequestSchema, async () => {
return {
resources: [
{
uri: "nvim://current-buffer",
name: "Current Neovim Buffer",
description: "The currently active buffer in Neovim",
mimeType: "text/plain",
},
{
uri: "nvim://open-buffers",
name: "Open Neovim Buffers",
description:
"List of all open buffers in Neovim instances running in current directory",
mimeType: "application/json",
},
],
};
});
/**
* Read resource content
*/
server.setRequestHandler(ReadResourceRequestSchema, async (request) => {
const uri = request.params.uri.toString();
if (uri === "nvim://current-buffer") {
const current = await getCurrentBuffer();
if (!current) {
return {
contents: [
{
uri,
mimeType: "text/plain",
text: "No Neovim instance found in current directory",
},
],
};
}
return {
contents: [
{
uri,
mimeType: "text/plain",
text: `Path: ${current.path}\n\n${current.content}`,
},
],
};
}
if (uri === "nvim://open-buffers") {
const buffers = await listOpenBuffers();
return {
contents: [
{
uri,
mimeType: "application/json",
text: JSON.stringify(buffers, null, 2),
},
],
};
}
throw new Error(`Unknown resource: ${uri}`);
});
/**
* List available tools
*/
server.setRequestHandler(ListToolsRequestSchema, async () => {
return {
tools: [
{
name: "list_nvim_buffers",
description:
"List all open buffers in Neovim instances running in the current directory",
inputSchema: {
type: "object",
properties: {},
},
},
{
name: "get_current_buffer",
description: "Get the currently active buffer in Neovim",
inputSchema: {
type: "object",
properties: {},
},
},
{
name: "get_buffer_content",
description: "Get the content of a specific buffer by path",
inputSchema: {
type: "object",
properties: {
path: {
type: "string",
description: "The file path of the buffer",
},
},
required: ["path"],
},
},
{
name: "update_buffer",
description:
"Update the content of a buffer in Neovim. Changes appear immediately in the editor.",
inputSchema: {
type: "object",
properties: {
path: {
type: "string",
description: "The file path of the buffer to update",
},
content: {
type: "string",
description: "The new content for the buffer",
},
},
required: ["path", "content"],
},
},
{
name: "reload_buffer",
description:
"Reload a buffer from disk. Use this after editing a file externally to refresh the buffer in Neovim.",
inputSchema: {
type: "object",
properties: {
path: {
type: "string",
description: "The file path of the buffer to reload",
},
},
required: ["path"],
},
},
{
name: "reload_all_buffers",
description:
"Check all open buffers and reload any that have changed on disk. Use this after editing files externally.",
inputSchema: {
type: "object",
properties: {},
},
},
{
name: "open_file",
description:
"Open a file in Neovim. Use this to open newly created files or existing files for editing.",
inputSchema: {
type: "object",
properties: {
path: {
type: "string",
description:
"The file path to open (can be absolute or relative to current directory)",
},
},
required: ["path"],
},
},
],
};
});
/**
* Handle tool calls
*/
server.setRequestHandler(CallToolRequestSchema, async (request) => {
const { name, arguments: args } = request.params;
try {
if (name === "list_nvim_buffers") {
const buffers = await listOpenBuffers();
return {
content: [
{
type: "text",
text: JSON.stringify(buffers, null, 2),
},
],
};
}
if (name === "get_current_buffer") {
const current = await getCurrentBuffer();
if (!current) {
return {
content: [
{
type: "text",
text: "No Neovim instance found in current directory",
},
],
};
}
return {
content: [
{
type: "text",
text: `Current buffer: ${current.path}\n\n${current.content}`,
},
],
};
}
if (name === "get_buffer_content") {
const content = await getBufferContent(args.path);
return {
content: [
{
type: "text",
text: content,
},
],
};
}
if (name === "update_buffer") {
const result = await updateBuffer(args.path, args.content);
return {
content: [
{
type: "text",
text: `Successfully updated buffer: ${result.path}`,
},
],
};
}
if (name === "reload_buffer") {
const result = await reloadBuffer(args.path);
return {
content: [
{
type: "text",
text: `Successfully reloaded buffer: ${result.path}`,
},
],
};
}
if (name === "reload_all_buffers") {
const result = await reloadAllBuffers();
return {
content: [
{
type: "text",
text: result.message,
},
],
};
}
if (name === "open_file") {
const result = await openFile(args.path);
return {
content: [
{
type: "text",
text: `Successfully opened file in Neovim: ${result.path}`,
},
],
};
}
throw new Error(`Unknown tool: ${name}`);
} catch (error) {
return {
content: [
{
type: "text",
text: `Error: ${error.message}`,
},
],
isError: true,
};
}
});
// Start the server
const transport = new StdioServerTransport();
await server.connect(transport);
console.error("Neovim MCP server running on stdio");
}
main().catch((error) => {
console.error("Fatal error:", error);
process.exit(1);
});
