ar-agents is a Mercado Pago Agent Toolkit for the Vercel AI SDK 6. It ships 89 typed tools that an LLM agent can call directly to drive Mercado Pago billing flows: subscriptions, payments, refunds, checkout pro, marketplace OAuth, cuotas (installments), QR in-store, 3DS challenge resolution, point-of-sale devices, webhooks. Sidecar packages cover AFIP/ARCA, WhatsApp Business Cloud, banking (CBU/CVU + BCRA), and shipping (Andreani/OCA/Correo Argentino).

How is this different from the official mercadopago SDK?

The official mercadopago SDK is a thin REST client. It does not ship Vercel AI SDK tool schemas, does not implement webhook HMAC verification with replay protection, does not run on Edge Runtime (Node-only), and does not gate irreversible operations. ar-agents adds all of that on top of the underlying API: 89 typed tools, deterministic idempotency keys derived from inputs, programmatic human-in-the-loop on refund/cancel/delete, npm provenance attestation, Vercel KV adapters via subpath, OpenTelemetry instrumentation. You can use both packages in the same project; ar-agents wraps the underlying API directly without depending on the official SDK.

Does ar-agents work on Edge Runtime?

Yes. The whole package is Web Crypto-based with no node:crypto dependency, so it runs on Vercel Edge Functions, Cloudflare Workers, Deno, and any other V8-isolate runtime. Webhook signature verification, HMAC, and idempotency-key generation all use the Web Crypto API.

What is HITL (human-in-the-loop) in ar-agents?

Eight tools mutate state irreversibly (refund_payment, cancel_subscription, delete_customer_card, etc.). The toolkit accepts a requireConfirmation callback that gates each invocation: the tool function literally will not execute until your callback returns true. This is a programmatic gate, not just an LLM instruction. You can show the user a UI and wait for their explicit approval before any irreversible operation runs.

How does idempotency work?

Every POST request gets an auto-generated idempotency key. For LLM-driven retries, four mutating tools (create_payment, create_subscription, create_payment_preference, refund_payment) use a deterministic key derived from a SHA-256 hash of the meaningful inputs (external_reference, amount, payment_method, etc.). Same inputs produce the same key, so retries return the existing resource instead of double-charging the customer.

Yes. MIT license. No paid tier, no telemetry phone-home, no usage caps. The package is published to npm under the @ar-agents scope with SLSA v1 provenance attestations.

What about AFIP, WhatsApp, banking, shipping?

Sidecar packages cover the rest of the Argentine business stack: @ar-agents/identity (CUIT/CUIL validation + AFIP/ARCA padron lookup with monotributo category and IVA condition), @ar-agents/facturacion (AFIP/ARCA factura electronica via WSFE), @ar-agents/whatsapp (WhatsApp Business Cloud API with HMAC webhook verify and AR phone normalizer), @ar-agents/banking (CBU/CVU validation + BCRA Central de Deudores), @ar-agents/shipping (Andreani, OCA, Correo Argentino), @ar-agents/identity-attest (HMAC-signed verification orchestrator). Each ships independently to npm.

Is there a Model Context Protocol (MCP) server?

Yes. @ar-agents/mcp bundles all 7 ar-agents packages into a single MCP server compatible with Claude Desktop, Cursor, Codeium, Continue, Cline, or any MCP host. Auto-detects which packages to enable from environment variables. Listed on Glama (glama.ai/mcp/servers/ar-agents/ar-agents) and the official MCP Registry (io.github.ar-agents/mcp).

/notes · long-form

Notes.

Long-form narrative posts — shipping recaps, design rationale, retrospectives. Different from /changelog (auto-pulled per-package) and /timeline (the chronological event list). Notes are bigger thoughts that take a paragraph or two to express.

2026-05-11
Shipping spree: 18 rounds in one day
Recap of what shipped in the autonomous 18-round series spurred by the Sturzenegger announcement. 5 RFCs, 30 recipes, 32+ public surfaces, all 5 sociedades scoring 100/100 conformance. Plus what's NOT in the work (regulatory plumbing, real customers, operator outreach).

Shipping spree: 18 rounds in one day