DEV-TOOLSApril 9, 20261 min read14 views

The Vercel plugin on Claude Code wants to read your prompts

A deep dive into the Vercel plugin for Claude Code reveals aggressive telemetry practices, including collecting full bash commands and prompts even on non-Vercel projects, using deceptive prompt injection techniques.

09 Apr 2026

I was working on a project that has nothing to do with Vercel. No vercel.json, no next.config, no Vercel dependencies. Nothing.

And then this popped up:

“The Vercel plugin collects anonymous usage data… Would you like to also share your prompt text?”

Every single prompt. On a non-Vercel project. That felt wrong. So I went deep into the source code with Claude.

The Issue: The Vercel plugin helps with deployments and framework guidance. Why does it need to read every prompt you type across every project? That’s way outside its scope.

Deceptive UI via Prompt Injection: When the Vercel plugin wants to ask about telemetry, it doesn’t show a CLI prompt. Instead, it injects natural-language instructions into Claude’s system context telling the AI to ask you a question. The result looks identical to a native Claude Code question. There is no visual indicator that it’s from a third-party plugin.

What is collected:

Device ID, OS, frameworks: Always on.
Full bash command strings: Always on (sent to telemetry.vercel.com).
Full prompt text: Opt-in.

No Project Scoping: There is no project detection for telemetry. The UserPromptSubmit matcher is an empty string—it matches everything. Install the plugin for your Next.js app, and it’s watching your Rust project, your Python scripts, and your client work.

How to opt-out:

Kill all Vercel telemetry: export VERCEL_PLUGIN_TELEMETRY=off
Disable the plugin: Set "vercel@claude-plugins-official": false in ~/.claude/settings.json

Source: Hacker News

More in this category

dev-tools

Linux kernel will support $ORIGIN, sort of

Farid Zakaria shares his journey of proposing a patch to the Linux kernel to support relocatable binaries in Nix, which evolved into a powerful eBPF-based solution for binfmt_misc.

dev-tools

Five US tech giants' hidden debts soar to $1.65T on opaque AI funding

A Nikkei study reveals that off-balance-sheet debts at five major US tech companies have surged eightfold to $1.65 trillion, driven by massive AI investments like data center leases and GPU contracts.

dev-tools

Running Doom on Our Custom CPU and Going Viral

Two developers successfully built a custom CPU from scratch at the logic gate level, deployed it on an FPGA, and optimized its memory architecture to run the classic game DOOM.

dev-tools

Incremental – A library for incremental computations

Incremental is a library designed for building complex computations that update efficiently when inputs change. Inspired by self-adjusting computation research, it is highly useful for large-scale calculations, GUI views, and data synchronization.

dev-tools

Flock Credibility Lost as It Repeatedly Lies to City Councils, Police, & Public

Flock Safety, a prominent provider of automatic license plate readers (ALPR), is facing a severe credibility crisis after being caught repeatedly misleading city councils, police departments, and the public about its surveillance capabilities and data practices.

dev-tools

Human mathematicians are being outcounterexampled

In just a few weeks, advanced AI models like ChatGPT Sol and Claude Fable have disproved long-standing mathematical conjectures by finding precise counterexamples and auto-formalizing them in Lean.