Launch HN: Vespper (YC F24) – SOTA Docx MCP

Sep 1, 2026 Research Launching Vespper DOCX MCP: 3× faster, 2× cheaper, more accurate Today we're launching Vespper DOCX MCP: the first model fine-tuned specifically for editing Word documents, shipped as an MCP. On our internal benchmark, it allows agents to be 3× faster, 2× cheaper, and more accurate than the closest alternative.

That work is increasingly shifting to agents. Microsoft Copilot and Claude in Word have made in-document AI mainstream, while a growing number of vertical agents; particularly in legal tech—need to interact with .docx files.

However, AI agents are still struggling to do great work in Word documents.

We spoke with dozens of software engineers, mostly in the legal tech and health care spaces, who said they spend weeks and even months tuning their harnesses to edit Word documents reliably, and now are forced to maintain very complex in-house solutions.