Initial setup notes and issue - ERROR spawn npx ENOENT during `wrangler secret put`

[tranqy]

Thanks for releasing this, excited to try it.

I'm going through the intro, a few notes.

Windows 11
Microsoft Powershell
Node installed via scoop

• The initial instructions fail unless I run npx wrangler login first
• Even then script fails to put the secret at the end
• The readme.md does not mention npm run deploy but npx workers-mcp help does. Someone has to use both to get running, but it's running.

I then went to the scripts and looked at

workers-mcp/src/scripts/secret.ts

Line 37 in 03dbf65

export async function uploadSecret(secret: string) {

I ran the command manually and it worked. Here's the error when run through the script.

[Puliczek]

I have the same problem.
Windows 11

[iAlan66]

I have the same problem.
Windows 10

[iAlan66]

Employing cross-spawn as a substitute for child_process appears to offer a viable solution to this predicament.

workers-mcp/src/scripts/utils.ts

Line 1 in 03dbf65

import { spawn } from 'child_process'

cross-spawn

[ranveer0323]

Same issue, @iAlan66 I couldn't find the src folder in the workers-mcp folder in node modules, where did you get it?

[duguyue8]

Encountered the same problem: x ERROR spawn npx ENOENT

[sligt83]

Same error message "spawn npx ENOENT". win10.

[5918vo]

./node_modules/.bin/workers-mcp docgen src/index.js

./node_modules/.bin/wrangler deploy

[omesh845]

Need to install the following packages:
workers-mcp@0.0.13
Ok to proceed? (y) Y


💪 Congratulations on installing workers-mcp 😎

┌  Let's get started...
│
●  Step 1: adding 'workers-mcp docgen src/index.ts' as part of your wrangler deploy step
│
◆  NPM script deploy already contains 'workers-mcp docgen'.
│  Keeping existing value:
│
│    "deploy": "workers-mcp docgen src/index.ts && wrangler deploy"
│
●  Step 2: generating and uploading a shared secret
│
◆  SHARED_SECRET already present in .dev.vars. It may already be uploaded.
│
▲  To reupload it, run npx workers-mcp secret upload manually.
│
●  Step 3: applying changes to src/index.ts
│  workers-mcp requires exporting a WorkerEntrypoint with a ProxyToSelf or ProxyToDO helper with each method annotated using JSDoc.
│
◇  For example, a "hello world" MCP Worker looks like
│
│  import { WorkerEntrypoint } from 'cloudflare:workers'
│  import { ProxyToSelf } from 'workers-mcp'
│
│  export default class MyWorker extends WorkerEntrypoint<Env> {
│    /**
│     * A warm, friendly greeting from your new Workers MCP server.
│     * @param name {string} the name of the person we are greeting.
│     * @return {string} the contents of our greeting.
│     */
│    sayHello(name: string) {
│      return `Hello from an MCP Worker, ${name}!`
│    }
│
│    /**
│     * @ignore
│     **/
│    async fetch(request: Request): Promise<Response> {
│      return new ProxyToSelf(this).fetch(request)
│    }
│  }
│
│
◆  Your src/index.ts seems to be already set up! Skipping...
│
●  Step 4: deploying your code!
Generated docs for src/index.ts in dist/docs.json
• MyWorker exported as default
  - sayHello(name: string): string
│
■  ERROR spawn npx ENOENT //-> struck here on step-4 error

//------------------------
package.json :
{
  "name": "my-mcp-worker",
  "version": "0.0.0",
  "private": true,
  "scripts": {
    "deploy": "workers-mcp docgen src/index.ts && wrangler deploy",
    "dev": "wrangler dev",
    "start": "wrangler dev",
    "test": "vitest",
    "cf-typegen": "wrangler types"
  },
  "devDependencies": {
    "@cloudflare/vitest-pool-workers": "^0.7.5",
    "@cloudflare/workers-types": "^4.20250319.0",
    "typescript": "^5.5.2",
    "vitest": "~3.0.7",
    "wrangler": "^4.2.0"
  },
  "dependencies": {
    "workers-mcp": "^0.0.13"
  }
}

[samdoeswork]

It's unfortunate that this project seems already abandoned. Not working on Windows at all is a pretty big issue.

[rudenko-programmer]

Hi everyone I have the same error on the step 4 what helps me (Win 11)

1. I have found claude setting via settings page

2. I have add all settings from scratch coz this file was empty

{
  "globalShortcut": "Ctrl+Space",
  "mcpServers": {
    "mcp-demo-1": {
      "command": "D:\\<Path to my project>\\mcp-demo-1\\node_modules\\.bin\\workers-mcp.cmd",
      "args": [
        "run",
        "mcp-demo-1",
        "https://mcp-demo-1.<my-domain-in-cloudflare>.workers.dev",
        "D:\\<Path to my project>\\mcp-demo-1"
      ],
      "env": {}
    }
  }
}

3. Reloaded claude and got new server in the chat, I got 401 as result but this is another issue