# Backwatch blog

- [The MCP sign-in chain, step by step](https://backwatch.dev/blog/mcp-sign-in-chain.md) (2026-11-04): What ChatGPT, Claude, Cursor, Codex and Gemini CLI do before a user sees your login page, and the five places it can break.
- [1 in 9 MCP servers that use sign-in break before a login page](https://backwatch.dev/blog/mcp-sign-in-study-2026-11.md) (2026-11-03): We checked 1,000 servers from the official MCP Registry. Of those that use sign-in, 11% fail before a user ever sees a login page, most often at the first step.