Block launches Buzz, a decentralized Slack alternative where AI agents work openly alongside humans

Block unveiled Buzz, a free, open-source workspace designed to let people and AI agents collaborate in ways that resemble Slack or Discord. The platform runs on Nostr, the decentralized messaging infrastructure long backed by Block founder Jack Dorsey as a censorship-resistant communication layer. Each AI agent operating in Buzz gets its own cryptographic identity tied to a human owner, creating what Block calls a verifiable "passport" for every bot.

The workspace itself feels familiar—channels, threads, direct messages, voice, media sharing, and code repositories all function much like existing team communication tools. What sets Buzz apart is how it reimagines agents: they participate as full members in conversations rather than as invisible background workers. Teams can integrate Claude Code, Codex, goose (Block's own framework), or any model that supports popular agent standards.

Why visible agent work matters#

Today's AI agent workflows happen mostly in the shadows. A team member spins up an agent, works privately for an hour, then pastes results back into a shared channel as if the work came from the person alone. According to Bradley Axen, Block's head of AI capabilities, this hidden conversation is where the most valuable technical decisions get made.

By bringing agents into shared workspaces, Buzz lets teams see how agents reason, make decisions, and interact with code—turning what was once invisible labor into something reviewable and discussable.

Cryptographic identity and control#

On Nostr, every participant fundamentally consists of a public-private keypair. Buzz assigns each agent its own keypair, but adds a crucial second signature that links the agent back to its human owner.

"It starts like a human. It's just got its own public key, and it signs events, and then there's one extra message that we publish on the relay," Axen explained. "We've got this cryptographic paper trail that neither of us could have done alone that says, okay, this is my agent, and anyone else can review and confirm that that's true."

This approach allows workspaces to enforce granular rules—for example, restricting access to private channels only to agents owned by team members. Block has proposed this identity scheme as an extension to Nostr itself, though upstream adoption remains pending.

Agents connect through the Agent Client Protocol (ACP), an open standard released by Zed for integrating coding agents across tools. Axen serves on the steering committee of the Linux Foundation's and indicated the foundation is considering adopting ACP.