ThoughtStack is an AI-powered research workspace built for founders and builders who want organized thinking, not scattered chat transcripts. Instead of a single endless conversation you'll lose track of, ThoughtStack's agent works alongside you and automatically organizes everything into structured, reusable Thought cards — the ideas, decisions, and research that actually matter, saved and searchable, not buried in scrollback.

Start from a guided workflow instead of a blank page. The agent does the digging — researching, synthesizing, and drafting — while you steer and edit. Every card stays in your workspace: revisit it, update it as things change, export it, or share a read-only link with collaborators.

Pricing is pay-as-you-go with no subscriptions or hidden seats — you only pay for what the agent actually does, and a free demo is available instantly with no signup required.

ThoughtStack also connects directly to Claude, so your saved Thoughts carry context into every new conver