Coding agents are quietly locking companies into per-vendor config files — and the most prominent CEO in the AI-tooling conversation is pushing back.
Shopify CEO Tobi Lütke says he's considering banning Claude Code from the company unless Anthropic starts natively reading the shared AGENTS.md standard — a threat that has turned a one-line file format into an open fight over whose spec wins in the coding-agent market. In a post on X, Lütke said he would pull the tool unless Anthropic supports both AGENTS.md and .agents/skills, the same files already read by OpenAI's Codex, Cursor, Gemini CLI, GitHub Copilot, Devin, and VS Code.
The core complaint is what Lütke calls "split brain." Engineers at one company now run several AI coding tools side by side, and each only reads its own config folder. One agent knows how the tests run and which directories it must not touch; another, working on the same repo, has none of that context. "Today it's CLAUDE.md, tomorrow some other vendor's file — the more AI tools you add, the more fragmented the rules become." That fragmentation is why Shopify, a company that has baked AI fluency into performance reviews and now requires teams to justify any headcount AI can't cover, treats config portability as a hill worth fighting on.
Anthropic's Claude Code team member Thariq Shihipar hit back within hours, saying the company is making the tool "more modifiable" and easing access to AGENTS.md or other system-prompt settings. But he defended Claude Code's own CLAUDE.md / .claude/skills / .claude/rules structure, arguing that system prompts materially change how a model behaves and that different model families can't simply be swapped. For now, users can force Claude Code to load the shared file by adding a line to CLAUDE.md — a workaround that does little to resolve whose format becomes the default.
The tension is sharper than a mere feature request. AGENTS.md now lives in more than 60,000 open-source repos, and OpenAI donated it to the Linux Foundation's Agentic AI Foundation in December 2025 — a body Anthropic itself co-founded, having contributed the MCP protocol. The awkward part is that Anthropic helped stand up the open agent infrastructure while its marquee coding tool still refuses the shared file natively. The New Stack reported Anthropic had already closed the developer feature request for AGENTS.md support, making Lütke's ultimatum all the more pointed.
This is the quiet governance war of the agent era: the models get swapped all the time, but the rules, permissions, and workflows a company writes down are the actual moat — and whoever owns the file format controls it. Anthropic betting that a superior model beats an open standard is the central wager, and Shopify is the kind of flagship customer that tests it.
What to watch next: whether Anthropic folds native AGENTS.md support into the next Claude Code release, or holds its line and risks more big-ticket defections.
Is a single shared config standard good for the coding-agent market, or does it just hand the advantage to the biggest vendor? Tell us in the comments.
Sources: The New Stack · AGENTS.md feature request (GitHub) · Tobi Lütke on X · AI Era (Xin Zhi Yuan) · 36Kr
