"Information about queue-based systems or concepts" matching MCP servers:

Generate crypto QR codes (BTC, ETH, SOL, USDC, USDT, EURC) and manage payment sessions from Claude Desktop or any MCP client. Non-custodial, free.

Create invoices from any MCP client via the Invovate API — compute totals and generate PDF, JSON, or UBL invoices in 11 languages. Exposes four tools: calculate_invoice_totals (no API key needed), generate_invoice_pdf, generate_invoice_ubl, and get_invoice_capabilities.

Lets AI agents discover, pay for, and call any HTTP API per request using USDC, with gasless nanopayments and no API keys or accounts needed.

Enables querying MRR, churn, and revenue from Stripe, Gumroad, and Lemon Squeezy directly inside Claude, allowing natural language questions about business metrics.

Integrates usage-based billing into AI coding tools, enabling meter usage, signal verification, and billing management via the ClockNext API.

Yolfi Agent Kit for AI coding agents: receive crypto, SaaS payment, stablecoin checkout, payment links, payment status checks, webhook verification, and webhook-based access logic to applications through Yolfi

The MCP gateway that lets any AI agent discover and pay metered APIs on Base or Solana — without the user wiring payments themselves.

Enables agents to request payment authorization against signed human mandates, enforcing policy-as-code limits and returning a decision (authorize, challenge, or deny) without moving funds.

Read-only MCP server for the Swiss eBill portal, enabling users to list bills and download invoice PDFs via an authenticated browser session. It cannot approve, release, or pay anything.

Spending limits for AI agents. Create budgets, enforce limits, track spend across x402, cards, MPP, or any payment rail.

Enables interaction with the Crowns game API as MCP tool calls, including x402-based payments.

Enables AI assistants to operate the Ribbo recurring billing API, allowing them to manage subscriptions, check entitlements, refund payments, charge immediately, and generate payment or renewal links.

Enables AI agents to buy, hold, and transfer CPI-pegged FLAT stablecoin without wallets or gas. Provides tools for earning through tasks, trading, and managing balances via MCP.

Enables AI agents to autonomously pay for and discover services using HPP USDC.e over the x402 protocol, without API keys or manual signing.

Pay for any x402-gated content or API with USDC micropayments on Base. Discover payment gates, execute payments, and view transaction history.

Give your AI agent a prepaid card to pay per call for hundreds of paid services — no per-vendor signups or API keys.

Combines wallets, onramps, and payments via x402 to enable AI agents to autonomously discover and pay for services without API keys or complex setup.

MCP server for the x402 micropayment marketplace minia2a.uk, enabling AI agents to discover, call, and pay for 1,700+ services using USDC micropayments with no API keys or subscriptions. Supports registration, credits, service browsing, and autonomous calling with Claude Code auto-mode.

Fail-closed live-endpoint x402 router. Pay $0.01 USDC on Base, Solana, or Algorand for a live payable URL or an honest miss.

Enables users to connect bank accounts within a chat session using Sophtron's UCW widget and query account information, owner details, and transactions persistently.