Block, the US financial technology company behind Cash App and the Square payments platform, debuted Buzz on 21 Jul, a free, open-source collaboration platform where humans and AI agents share a single workspace.
Block Bets Enterprises Will Trust AI Agents with Their Own Keys
22 July 2026 - 11:37 CEST
By Stu Clelland
Buzz runs on Nostr, a decentralized social protocol where every user holds their own cryptographic keypair instead of a company-issued account. That includes AI agents: every participant in Buzz, human or agent, holds a keypair that belongs to them rather than to Block or any other platform. That means an agent's identity, history and permissions travel with it across any Nostr-compatible system instead of being tied to a vendor account or an API key, a credential a platform issues and can revoke at will. This portability cuts both ways: Block can revoke an API key in seconds, but nobody can revoke a stolen keypair, whoever holds it holds everything the agent is authorised to do. The workspace itself includes channels, threads, direct messages, voice, media sharing, code repositories and automated workflows.
Model-agnostic by design
Buzz doesn't lock teams into one model or agent framework. Agents built on Claude Code, Codex or goose all plug in the same way, as would a custom-built agent. Teams can self-host to keep the whole stack, data, relay and agents, under their own control, or run it on Block's hosted version instead.
"Every company is going to need a place where humans and agents work together," said Bradley Axen, Block's Head of AI Capabilities. "The question is whether that place is proprietary or open. We built Buzz because we believe it should be open."
Still tagged a prototype
The Buzz repository carries an Apache-2.0 licence, a permissive open-source licence that lets anyone use, modify and redistribute the code, including commercially, with minimal restriction. It had drawn more than 2,500 stars and 190 forks within a day of Tuesday's public debut, real early traction given the repository itself dates back to March, meaning Block built Buzz privately for months before making it public this week. Block's own repository metadata classifies the project's maturity as a prototype.
Block did not immediately respond to a request for comment on that classification or on how it safeguards against a compromised agent key.
The first real test for Buzz won't be a star count or a benchmark. It will be the first agent-held key that gets stolen, and whether Block or the team running that agent is the one left explaining it.
