Show HN: Filling PDF Forms with AI Using Client-Side Tool Calling

Show HN: Filling PDF forms with AI using client-side tool calling

SimplePDF released a Copilot demo that fills PDF forms via client-side tool calling; SimplePDF has 200k+ monthly users. PDFs stay in the browser, with parsing, rendering, and field detection local. The demo uses a DeepSeek V4 Flash proxy by default, with BYOK, cloud, or LM Studio options.

Why it matters: HKR-H/K/R pass: the client-side PDF-agent angle is specific, with a clear privacy mechanism and builder relevance. It sits in the 72–77 band as a useful product demo, not a major platform release.