A year ago I deleted @anthropic-ai/sdk from a project and wrote about 150 lines of TypeScript to replace it. The reason I gave myself was honest and boring. The SDK pulled node:fs/promises in through an agent-toolset module, which broke the browser bundle. I could have waited for a browser-clean entry point. Instead I hand-rolled an SSE parser and wrote a post about why . I filed that away as a bundler story. Then I read a line in a piece about tooling for forward-deployed engi...