DynamicWorkerExecutor RPC tool proxy returns empty objects in local dev (Miniflare) #13263
Description
What versions & operating system are you using?
- macOS 14 (arm64)
- Node 20.19.4
- wrangler 4.80.0
- @cloudflare/codemode 0.3.3
- miniflare 4.20260317.2 (via @cloudflare/vite-plugin 1.30.1)
Please provide a link to a minimal reproduction
https://github.com/aribn/cloudflare-rpc-repro
Describe the Bug
DynamicWorkerExecutor RPC tool proxy returns empty objects in local dev (Miniflare)
I'm building an AI chat tool that uses @cloudflare/codemode to execute AI-generated JavaScript in a sandboxed Dynamic Worker, with RPC-proxied tool functions callable from within the sandbox.
What works locally: Code execution, data variable injection via code string, console log capture — all fine.
What doesn't work: Tool functions passed via ResolvedProvider[] are never called. Calls to codemode.get_step(...) from within the sandbox return {} instead of actual data. Parent-side functions never execute.
I also tried the Record<string, Function> format (which logged the deprecation warning Passing raw fns to executor.execute() is deprecated. Use ResolvedProvider[] instead.) — same result.
On some attempts, the RPC setup causes a segfault (Received signal #11: Segmentation fault: 11) in Miniflare.
const executor = new DynamicWorkerExecutor({
loader: env.LOADER, // exists, type: object
timeout: 30000,
globalOutbound: null
});
// Tools are never called — sandbox receives {} for each call
const result = await executor.execute(normalizedCode, [{
name: 'codemode',
fns: {
get_step: async (args) => {
console.log('called'); // never appears
return workerGetStep(args.name, formState);
}
}
}]);Workaround: Passing [] as providers and injecting all data directly into the code string works. But this means we can't use RPC callbacks for operations that need parent-worker access (DB queries, API calls).
Environment: macOS, wrangler 4.80.0, @cloudflare/codemode 0.3.3, @cloudflare/vite-plugin, worker_loaders binding