Anthropic Is Tightening the Screws — First-Party Harness Access Now Blocked Too

Yesterday, Anthropic cut off Claude Pro and Max subscriptions from working with third-party tools like OpenClaw. Today, it's getting worse. Developer Peter Steinberger shared on X that even first-party harness use is now returning 400 errors: claude-p --append-system-prompt 'A personal assistant running inside OpenClaw.' → 400 Third-party apps now draw from your extra usage, not your plan limits. The message is crystal clear: if you're not using Claude through Anthropic's own interfaces, you pay extra. Your subscription doesn't cover it anymore.