If you build agents on Base, two things landed recently that are worth connecting.
First: Base shipped its own Agent Skills. There's now a base/skills repo with consolidated skills that teach an AI agent to connect to Base, deploy contracts, authenticate wallets, and run nodes — installed with one command via Vercel's npx skills CLI.
Second: that CLI is part of a fast-growing, cross-agent ecosystem most crypto devs haven't clocked yet. So this post does two things — explains how npx skills and skills.sh actually work, and shows where the payment layer in Base's skills stops and how to extend it with x402 pay-per-call and batch disbursement.
What npx skills actually is
npx skills is an open CLI from Vercel Labs for installing "skills" — modular SKILL.md files that teach an agent a specific capability without stuffing everything into its context window. A few things make it different from what crypto devs usually expect:
-
GitHub is the registry. There's no central package server. Any public GitHub repo with a
SKILL.mdat its root is a valid, installable skill. Install withnpx skills add owner/repo. - It's cross-agent. The same skill installs into Claude Code, Cursor, Codex, GitHub Copilot, Goose, Windsurf, Gemini, and dozens more. You write once; it works across the agent you (or your users) actually run.
-
skills.shis the directory + leaderboard. It ranks skills by real install counts pulled from telemetry, with all-time, trending, and hot lists. There's no editorial submission step — you publish by putting a skill in a repo, and installs surface it.
The format underneath — SKILL.md — is an open spec, which is why Base, Vercel, Anthropic, and a long tail of independent devs all use the same files.
Here's Base's install, for reference:
# Base's official agent skills
npx skills add base/skills --skill build-on-base
npx skills add base/skills --skill base-mcp
build-on-base is a consolidated Base dev playbook; base-mcp wires up a Base MCP server that gives an agent a wallet — sending, swapping, signing, batched calls, balances.
Where Base's skills stop
This is the interesting gap. Base's skills give an agent a wallet and the ability to transact: send a payment, swap a token, sign, batch several calls into one transaction. That's the on-chain action layer, and it's well covered.
What that layer doesn't do is two distinct things the agent economy actually runs on:
Pay-per-call consumption. When an agent needs to buy data or compute — a price feed, a web search, an LLM completion — it needs to pay for that call, per call, without an API key or a billing account. That's x402: the HTTP 402 "Payment Required" status code turned into a machine-readable micropayment handshake. The agent hits an endpoint, gets a 402 with a price, signs a USDC authorization, retries, and gets the data. No signup.
Batch disbursement. "Batched calls" (bundling operations into one tx) is not the same as paying many different recipients in one transaction — payroll, airdrops, contributor payouts, refunds. That's a disbursement primitive, and it's what the Batch Payments for Agents (BPA 1.0) spec standardizes.
Both settle in USDC on Base. Neither is something a wallet-only skill handles. So they're a clean, complementary layer to drop on top of what Base ships.
Adding the payment layer
I published three skills that fill exactly that gap, each its own repo so you install only what you need:
- defi-intelligence-x402 — pay-per-call data + market intelligence on Base (prices, oracles, swap quotes, wallet analytics, ENS/Basename)
- ai-compute-x402 — pay-per-call AI inference (200+ LLMs, Bittensor, image gen, embeddings, GPU)
- agent-payments-x402 — batch payments, payroll, invoicing, escrow (BPA 1.0)
# Pay-per-call data + market intelligence on Base
npx skills add plagtech/defi-intelligence-x402
# Pay-per-call AI inference (200+ LLMs, Bittensor, GPU)
npx skills add plagtech/ai-compute-x402
# Batch payments, payroll, invoicing, escrow (BPA 1.0)
npx skills add plagtech/agent-payments-x402
All three call the Spraay x402 Gateway, which is x402-native end to end — no API keys, no accounts. You fund a wallet with USDC on Base, set one env var, and the x402 client signs and retries payments automatically.
npm install x402-client
export EVM_PRIVATE_KEY=0x... # wallet holding USDC on Base
Worked example: an agent that prices before it acts
A read call costs a fraction of a cent and needs no key:
import { createClient } from "x402-client";
const client = createClient({
baseUrl: "https://gateway.spraay.app",
privateKey: process.env.EVM_PRIVATE_KEY,
});
// Live oracle prices — pays ~$0.008 USDC, automatically
const prices = await client.get("/api/v1/oracle/prices");
// { ETH: 2847.50, BTC: ... }
// Profile a wallet before interacting with it
const profile = await client.get("/api/v1/analytics/wallet?address=0xabc...");
Worked example: pay 50 people in one transaction
This is the disbursement primitive a wallet-only skill can't express:
// Batch-send USDC to many recipients in a single tx
const tx = await client.post("/api/v1/batch/execute", {
chain: "base",
token: "USDC",
recipients: [
{ address: "0xabc...", amount: "10.00" },
{ address: "0xdef...", amount: "25.50" },
// ...up to your full roster
],
});
Estimate first with /api/v1/batch/estimate (≈$0.001) if you want a gas/fee preview before sending.
Why this matters for agents on Base
The mental model is two layers:
- Base's skills = the agent has a wallet and can transact.
- x402 skills = the agent can pay for each call it makes, and pay many parties at once.
Put them together and you have an agent that can read on-chain state, buy the data and compute it needs per call, and disburse funds — all in USDC on Base, all without a single API key or account. That's most of what an autonomous economic agent actually needs to do a job end to end.
If you're building on Base, the install lines above are the fastest way to try the payment layer. Skills are just SKILL.md files — open them before you install (it takes 30 seconds) and you'll see exactly which endpoints get called and what they cost.
Skills: agent-payments-x402 · defi-intelligence-x402 · ai-compute-x402
Links: Spraay Gateway · Docs / full endpoint catalog · Live gateway traffic · BPA 1.0 spec
