Robin

Posted on Feb 21

Cursor + Claude Max Ban: What Broke and How to Fix It

#ai #cursor #vscode #claudemax

Cursor's built-in Claude integration stopped working for developers on Claude Max subscriptions in January 2026.

If you're seeing auth errors, "subscription required" messages, or Claude responses failing silently in Cursor — this is why, and here's the fix.

What broke and why

Cursor integrates with Claude through Anthropic's API. When you connected Cursor to Claude via your Claude Max subscription, it was using an OAuth token from your consumer account. Anthropic's January 2026 enforcement blocked that path — automated tool access isn't permitted on consumer subscriptions.

What Cursor needs is an API key, not a subscription credential. The Anthropic API itself was never restricted — only the consumer OAuth token path was blocked.

Fix 1: Direct Anthropic API key (simplest)

If you just want Claude back in Cursor without any additional routing:

Get an API key from console.anthropic.com
In Cursor: Settings → Models → API Keys → Add Anthropic key
Select claude-opus-4-6 or claude-sonnet-4-6 as your model

That's it. You're now on the official API path with no subscription restriction. You pay per token instead of a flat monthly fee.

Cost reality check: For typical Cursor usage — code completions, chat, composer — a developer hitting Cursor heavily runs about 500K-2M tokens/month. At Sonnet-class pricing, that's roughly $3-15/month. Cheaper than most subscriptions for moderate users.

Fix 2: OpenAI-compatible endpoint (smart routing)

Cursor also supports a "Custom API" option that accepts any OpenAI-compatible base URL. This lets you use a routing layer that automatically picks the right model per request.

Setup:

Cursor Settings → Models → Custom → Enable
Base URL: https://www.komilion.com/api/v1
Model: neo-mode/balanced (auto-routes) or neo-mode/premium (Opus 4.6)
API Key: your Komilion key

Why use routing vs. direct API?

With direct API, you're pinning to one model and paying that model's rate for everything. A quick "explain this function" costs the same as a complex refactor.

With routing, a classifier reads each request and sends it to:

Fast cheap models for short questions and completions (~$0.006/req)
Balanced models for most coding tasks (~$0.10/req)
Opus 4.6 direct for architecture and complex multi-file work (~$0.55/req)

For Cursor's mix of quick completions + deep composer sessions, this typically cuts the bill 50-70% vs. Opus on everything.

What still works vs. what doesn't

When using a custom OpenAI-compatible endpoint in Cursor, most features work:

Feature	With custom API
Cursor Chat	✅ Full support
Code completions	✅ Full support
Composer (multi-file edits)	✅ Works
Cursor Tab (inline completions)	⚠️ May use local model, not custom API
`@codebase` context	✅ Full support
Terminal Cmd+K	✅ Full support

Cursor Tab (the "ghost text" completions) uses a separate model path that may not go through the custom API. Everything else — chat, composer, Ctrl+K in editor — routes through your configured API.

Choosing between models in Cursor

When using neo-mode/balanced, the routing layer handles model selection automatically. The three Komilion model strings:

Model: neo-mode/frugal               → Auto-route, cheapest capable
Model: neo-mode/balanced             → Auto-route, smart default
Model: neo-mode/premium              → Auto-route, always frontier model (Opus 4.6)

For direct Anthropic API (Fix 1 path, not Komilion):

Model: claude-opus-4-6               → Opus 4.6
Model: claude-sonnet-4-6             → Sonnet 4.6

For Cursor's composer (long multi-file sessions), neo-mode/premium or Opus direct tends to produce the most complete output. For quick questions and chat, neo-mode/balanced is the better default.

The cost math for Cursor users

The Claude Max subscription was $20-100/month flat. Here's how API pricing compares for typical Cursor usage:

Usage level	Cursor Max subscription	Direct Opus API	Smart routing (balanced)
Light (quick questions, completions)	$20/mo	~$5/mo	~$2/mo
Moderate (daily coding, composer)	$20-100/mo	~$25/mo	~$8/mo
Heavy (all-day multi-file sessions)	$100/mo + limits	~$80/mo	~$25/mo

The break-even is moderate-heavy usage. Light to moderate Cursor users pay less with API access, not more.

Quick setup (30 seconds)

Cursor Settings (Cmd+,) → Models → Custom API:

Base URL: https://www.komilion.com/api/v1
API Key:  your-key-here
Model:    neo-mode/balanced

$5 free credits at komilion.com — no card required. Full Cursor migration guide at komilion.com/cline.

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