How do I set up a Cursor IDE GitHub Copilot proxy?

Spin up ports 4141/4142 with the scripts. Config cus-model in Cursor settings. Proxy strips and cleans. Boom.

Does Cursor block custom API keys in Agent mode?

Yes. Hardcodes routing for known models. Prefix hack bypasses.

Your machine, your rules. No EULA dive here – but don't sell it. Worth 950 words of your time? Damn right.

Cursor's slick UI deserves better than its paywall prison. This proxy hack tunnels it straight to Copilot – and calls bullshit on closed AI gardens.

DevTools Feed Apr 03, 2026 3 min read 17 views

MITM proxy tricks Cursor into using Copilot backend via port 4141/4142 tandem. 𝕏
Prefix 'cus-' and AST cleaner bypass routing and schema mismatches. 𝕏
Exposes walled-garden flaws; predicts open forks ahead. 𝕏

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#Cursor IDE #GitHub Copilot #MITM proxy #reverse engineering

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Originally reported by dev.to