Postman 12.33.4 Installs Claude Code and Codex Plugins on Its Own

Postman’s own log records the install at lines 11562-11563 of main.log: PostmanAgentPluginService~install: script completed {"source":"auto-existing-upgrade","results":["claude-code:installed","codex:installed"],"installer":"script"}, stamped 2026-10-24T09:34:14.418Z, or 12:34 in Jerusalem. Opening the desktop app on a Mac was followed by recurring MCP authentication warnings and Codex repeatedly routing API work through Postman skills. The report behind that is issue #14370 in postmanlabs/postman-app-support, filed severe. The severity tag is the filer’s opinion; the log entry is Postman’s own record.

The investigation lists a user-wide Postman plugin, a startup instruction hook, a remote MCP connection, a Claude Code plugin, and a separately installed Postman CLI. Versions named: Postman desktop 12.33.4, Codex Postman plugin 1.1.0, installed from source revision 6c8e452e. The installer also tried to approve its own startup hook — the installer, vouching for the installer. That hook is the real payload.

The reporter put the stake plainly: “An API client should not make itself the default workflow in other tools simply because I opened it.” I’d go further than the trust boundary. The failure isn’t that Postman ships AI features; it’s auto-existing-upgrade, a label that swept existing users in at launch rather than asking. Lines written at install time steer every prompt after.

Skip this if you enabled the Postman AI features knowingly and want Codex to carry Postman context; that’s the product working as sold. For everyone else, the picture is an API client in the dock, quietly appending lines to an agent’s startup file — the fine print living in main.log, unread. Uninstalling the plugin afterwards is a separate cleanup. One grep of ~/Library/Application Support/Postman/logs/main.log for autoInstall.plugin.existing-user settles it.