There are now 50,800 agents with a registered onchain identity on Ethereum mainnet. Not wallets, not tokens — agents, recorded against the ERC-8004 Identity Registry, checked as of September 14. That number only moves in one direction: registries don't un-register an agent, so 50,800 is a floor for how many onchain-identifiable agents exist today, not a peak.
That's the headline. Here's the rest of the week's pulse on the builder library.
The library right now
SatoHub is tracking 382 resources builders actually reach for. MCP servers are the single biggest category by a wide margin — 135 of the 382, more than a third of the entire library — followed by API/SDK tooling (45), agent frameworks (29), trading tools (28), skill repos (27), wallet infrastructure (26), and data tools (24). Developer tooling (20), DeFi tools (18), and security tools (10) round out the working stack. Onchain agents themselves — the deployed, autonomous things, as opposed to what you build them with — stay a deliberately small slice: 6 listed, plus 6 agent marketplaces and 3 launchpads. That ratio is the point: SatoHub is a builder hub, and the builder-with layer dwarfs the built-agent layer, same as any healthy tool ecosystem dwarfs its finished products.
By chain, multichain tooling leads (136), which tracks — most SDKs and MCP servers don't lock to one network. Base (125) and Ethereum (103) are next, with Solana close behind at 94. Arbitrum (54), Polygon (47), and BNB Chain (40) fill out the rest, and 39 resources don't declare a chain at all.
The identity layer, in numbers
Back to that 50,800. ERC-8004 gives an agent a portable, onchain identity — a registry entry other agents (or humans) can check without trusting a central issuer. We don't have a prior week's count to diff against, so we won't dress this up as a growth rate we can't show our work on. What we can say: it's a real, checkable number on Ethereum mainnet, not a claim in a deck. That's the difference between "trust me" and "check the registry" — and it's the entire reason ERC-8004 exists.
This week's Sato Score leaders
The Sato Score is a transparency and liveness read — how open, active, and verifiable a resource's evidence trail is. It is not a safety grade, a quality grade, or a signal about returns. With that framing locked in, six builders are sitting in the High tier above 85 this week: Raydium (95), BlockRun MCP (89), Coinbase AgentKit (88), TradingAgents (88), ElizaOS (87), and GOAT SDK (87). A high score means the evidence is there to check — active repos, real docs, a verifiable track record. It's a starting point for due diligence, not a substitute for it.
Newest to the library
Six additions landed in the past two days: minia2a (agent marketplace, Sept 13), Ogena token risk (data tool, Sept 13), Robinhood Trading MCP (MCP, Sept 12), Pons (DeFi tool, Sept 12), hood.fun (DeFi tool, Sept 12), and Pools.trade (DeFi tool, Sept 12). Three of six are DeFi tooling landing the same day — worth watching whether that's a cluster or a coincidence next week.
Notable moves
Three things worth a second look. unbrowse shipped two point releases back to back (v11.4.4 and v11.4.3), the kind of rapid-iteration cadence that's a decent proxy for an actively maintained project. openclaw pushed 2026.9.4. And Decrypt ran a piece worth reading against the identity-registry number above: ["AI Agents Spending Money Online? New Research Says Not Really"](https://decrypt.co/378103/ai-agents-spending-money-research) — a useful counterweight to any narrative that agentic commerce is already at scale. Registering an identity and spending money autonomously are two very different milestones, and it's worth not conflating them.
What to watch
Next week we'll have a real week-over-week number on the ERC-8004 count instead of a single snapshot, and it's worth watching whether the DeFi-tool cluster in this week's additions continues. Both are things you can check yourself, not things you have to take our word for.
If you're building a crypto agent right now, the stack above is the supply layer underneath it — wallets, payment rails, MCP servers, frameworks, all mapped and scored. Describe what you're building and see the pieces: [build your agent at satohub.ai/build](https://satohub.ai/build).