Mediator.ai - Private AI assistants for collaborative document drafting and negotiation

What it does

Mediator.ai is a collaborative document editing platform that gives each participant a private AI assistant. Users can draft contracts, proposals, or agreements together in one live document while keeping their strategy, notes, and files private. The AI, built on GPT-5.4, can rewrite paragraphs in place, weigh options, or explain changes—all without other participants seeing the interaction. The platform also tracks changes with attribution and history, and allows marking paragraphs as agreed.

Who it is for

Mediator.ai is designed for professionals who need to negotiate or draft sensitive documents collaboratively. Use cases include co-founder agreements, client proposals, contract revisions, parenting plans, and sensitive internal drafts. It is particularly suited for situations where parties have conflicting interests and need to keep their negotiation strategies private while working on a shared document.

Why it matters

Traditional collaborative tools like Google Docs or Notion offer a single shared AI assistant, meaning every query is visible to all participants. This is impractical for negotiations where each party has private priorities and constraints. Mediator.ai solves this by providing a private assistant for each person, enabling honest exploration of options without revealing strategy. The platform also eliminates version confusion from email-based draft exchanges by maintaining a single live document with full change history.

Launch signal

Mediator.ai was launched on Hacker News as a Show HN post with the title "Show HN: Mediator.ai – Using Nash bargaining and LLMs to systematize fairness." The website is live and functional, offering a pay-as-you-go pricing model with no subscription or seats. Users can start a document for free and only pay for AI usage (e.g., redrafting a paragraph). The platform is built on GPT-5.4.

Brand and naming

The name "Mediator.ai" directly communicates the product's purpose: acting as a neutral third party to facilitate fair negotiations. The tagline "Using Nash bargaining and LLMs to systematize fairness" references the Nash bargaining solution from game theory, positioning the product as mathematically grounded. The brand emphasizes privacy and strategy, with messaging like "The document is shared; your strategy stays yours."