Sponge

About Sponge

Sponge is a deep-research harness that runs on your machine. Sponge Library, its hosted part at sponge.computer, is a private library for the articles and PDFs you read. It saves a dated, readable copy of each page, keeps your highlights and notes beside it, and lets your AI agent read and cite those sources through the API.

Write a note or use your own agent to investigate a question. Read the sources, compare conflicting findings, and decide which changes to keep. Your research can remain private, become a shared document, or contribute to a reviewed public edition.

An answer should remain understandable after the conversation ends. Sponge keeps document history, cited evidence, and review decisions so a later reader can inspect how the work reached its conclusion.

People direct the work

Your agent can help search, draft, compare, and challenge. People choose the question, evaluate the evidence, and decide what to share. Accepting an agent proposal does not publish it, and a saved source does not make a claim true.

Sponge is built by Hraness. Hraness is a software studio that makes tools for AI agents and for people, from agent memory to music. Most are open source. Sponge’s longer-term direction is a body of public research that people can inspect, cite, and build on, while retaining control of their private work.

Try one question

Start a private document or follow the first steps. The status page explains current availability and limits.

Contact and privacy

Find product and account help, or read Privacy for what stays private, who can see what you share or publish, and what analytics and the newsletter collect.