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setup-learning.ts fails on Windows with "spawn npx.cmd EINVAL"

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@Caldas is already working on this.

Since Oct 14, 2026.

  • #793 by @Caldas — open

Assessment

Difficulty
2/5
Estimated time
1-3 hours
Newbie friendliness
80/100
Issue type
Bug
Clarity
Clearly specified
Activity status
Active
Tech stack
nodejs, typescript
Domain
backend, cli

Research direction

Start with runCli in server/src/learning/ensure-container.ts (around lines 124-149), where spawn is called without shell on Windows, and trace the entry from scripts/setup-learning.ts. Reproduce on Windows with bun scripts/setup-learning.ts to see the EINVAL, and check that the child.on("error") handler is bypassed. Done when the setup script runs on Windows and the CLI commands succeed, with macOS and Linux behaviour unchanged.

Written by the indexing model from the issue text.

Description

On Windows, bun scripts/setup-learning.ts (Quick start, step 2) stops before doing anything, and prints only this:

PS C:\...\openbot> bun scripts/setup-learning.ts
spawn npx.cmd EINVAL

npx --yes copilotkit@latest login and project select had both succeeded beforehand, from the OpenBot root. Nothing is written to .env, so neither the runtime key nor the openbot Learning container is set up.

Cause

runCli in server/src/learning/ensure-container.ts:124-149 starts the CopilotKit CLI like this:

const child = spawn(
  process.platform === "win32" ? "npx.cmd" : "npx",
  ["--yes", "copilotkit@latest", ...args],
  { cwd: directory, env: cliEnvironment(), stdio: ["ignore", "pipe", "pipe"] },
);

Since the fix for CVE-2024-27980, Node refuses to spawn a .cmd or .bat file without shell: true, and Bun does the same. The refusal is a synchronous EINVAL thrown by spawn() itself, not an 'error' event. As a result, the child.on("error", () => finish(127)) handler at line 147 never runs. The throw happens inside the Promise executor, so it becomes a rejection, and setup-learning.ts exits with the bare message.

Minimal reproduction, Bun 1.4.3 on Windows 11:

import { spawn } from "node:child_process";
spawn("npx.cmd", ["--version"]);                 // throws: spawn npx.cmd EINVAL
spawn("npx.cmd", ["--version"], { shell: true }); // runs, prints 11.19.0

The server calls the same runCli from ensureLearningContainer at boot (server/src/index.ts:360) when a CLI login is present. Automatic container creation should therefore fail the same way on Windows, although I have only reproduced it through the setup helper.

Suggested fix

Run through the shell on Windows only:

{
  cwd: directory,
  env: cliEnvironment(),
  shell: process.platform === "win32",
  stdio: ["ignore", "pipe", "pipe"],
}

With shell: true the arguments are joined into a cmd.exe command line rather than passed as an argv. That is safe here because every caller passes literals (whoami, project list --json). cliEnvironment() already keeps COMSPEC, SystemRoot and PATHEXT, so cmd.exe resolves. macOS and Linux are unchanged.

Windows 11 Enterprise 10.0.26200, Bun 1.4.3, Node 24.21.0 / npm 11.19.0, OpenBot at 8c9ad4c. Related: #679 and #681 (other Windows checkout problems).

Dominant language
TypeScript
Stars
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Forks
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Avg merge
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Merged PRs (30d)
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