Block's Buzz gives your AI agents their own identity

Block launched Buzz today — an open-source workspace where humans and AI agents share the same channels, threads, and DMs. The Slack-competitor headline is the least interesting thing about it. The part worth your attention: every participant, human or agent, holds its own cryptographic keypair, and agent actions carry a signature tracing back to the human who owns them.

What actually happened

Per Block's announcement, Buzz builds identity on Nostr, a decentralized protocol of cryptographically signed events. Block's framing is that Nostr "solves the most fundamental problem in multi-agent collaboration: identity." An agent's keypair belongs to the agent, not to a platform account or a vendor-managed API key — Block calls it "portable, verifiable, and independent."

Agents aren't bolted-on bots that wait for slash commands. They're workspace members that can search discussions, submit patches, review code, and run workflows using the same primitives humans use. The platform is model- and harness-agnostic, shipping with support for Claude Code, Codex, and goose, plus the option to bring your own.

It's Apache-2.0 at github.com/block/buzz, free, and available either self-hosted on your own infrastructure or through Block's hosted version. Jack Dorsey described it as "model-agnostic, decentralized, self-sovereign, and open source." TechCrunch notes Buzz itself admits it's in early stages, and Block flags the Git integration specifically as "still early." Don't migrate your team this week.

Why agent identity matters for your business

Here's the problem Buzz is pointed at, and you have it whether or not you ever install this thing. The moment you run more than one agent, you lose the audit trail. A record got updated, an invoice went out, a config changed — and your logs say service-account-prod did it. That account is shared by four automations and two contractors. Good luck.

Shared API keys are the default because they're the path of least resistance, and they collapse exactly when you need them: during an incident, a dispute, or an audit. Per-agent identity with a chain of custody back to a human owner is the fix, and it's cheap to adopt early and miserable to retrofit after you've got a dozen automations sharing one token.

You don't need Nostr or Buzz to take the lesson. Issue each automation its own credential. Scope it to the minimum it needs. Log which agent did what, under whose authority. Make revoking one agent a five-minute job that doesn't break the other eleven. Whether Buzz wins against Slack is a coin flip — Block has abandoned bets before — but the identity model it's arguing for is where governance is heading, and you can implement it Monday on whatever stack you already run.

Sources: Block, TechCrunch.