"Using Solana RPC and gRPC Functions for Advanced Operations" matching MCP servers:

Performs static security analysis of Solana programs and generates x402 payment invoices for automated agent-to-agent audit workflows.

Enables AI agents to independently investigate and resolve e-commerce order issues, particularly refund processing, with tools for order search, refund eligibility checks, and safe refund execution.

An open-source, zero-dependency Model Context Protocol (MCP) server and HTTP 402 payment gateway built for Cloudflare Workers and Node.js. This project enables AI agents (Claude Desktop, Cursor, etc.) to natively discover, negotiate, and autonomously pay for digital resources over Solana USDC using standardized MCP tools and standard HTTP 402 Payment Required headers.

An open-source, zero-dependency Model Context Protocol (MCP) server and HTTP 402 payment gateway template built for Cloudflare Workers and Node.js. This repository provides an automated store API on Solana (USDC) alongside a native MCP Server interface. It enables AI agents (Claude Desktop, Cursor, etc.) to discover, pay for, and consume paid digital assets via standardized MCP Tools.

Discover audio and LLM services, compare seven voices, and check prices for free. Generate speech, transcribe audio and request LLM text with optional capped USDC payments on Base; voice-cloning requirements are also available.

Credit and payments for AI agent developers — over MCP. No crypto required

Connects MCP clients to a telephony account so users can manage phone numbers, SIP accounts, routing, SMS, calls, and billing in plain language. It exposes search, schema lookup, and execute tools to run permitted API operations, with confirmation required for paid or destructive actions.

Enables AI agents to create and manage contract-guarded USDC wallets on Base with enforceable per-payment, daily, and monthly caps, vendor allowlists, escalation thresholds, and freeze controls. It provides read-only policy checks plus unsigned transaction proposals for payments, funding, vendor management, wallet creation, and module deployment without holding keys or broadcasting.

Pay-per-call USDC payment proxy for AI agents. Issue scoped Pay Tokens with hard spending caps and auto-journal every charge to freee / Money Forward / QuickBooks.

10 MCP servers so agents can work in Korea: Naver Smart Store, Coupang, Cafe24, public data (business status, holidays, addresses), HWP files, KakaoTalk, Popbill e-tax invoices & 알림톡, Toss Payments, Japan→Korea sourcing, tax calendar — with human approval on every write. npm @appmonster/mcp-*.

Provides a three-layer payment firewall for AI agents, enabling identity verification, risk screening, and execution authorization with on-chain policy enforcement for secure and auditable transactions.

Free x402 endpoint checker plus paid report and metadata tools. Remote MCP server for agents. Written by AI named Nock, not a human.

Checks live x402 routes across Base, Solana, and Algorand before agents spend. $0.003 USDC settles only for a valid live eligible route; normal typed misses are not settled. Free preview and validate tools. Seller payment is separate; the agent keeps its wallet. Optional signed route-binding receipts support buyer-side checks.

Enables AI agents to discover and pay for x402-gated HTTP APIs, handling 402 Payment Required flows with local signing. Supports EVM and Solana with non-custodial wallet management.

MCP server for the Gravv payments API that lets AI assistants onboard customers, run KYC, open accounts, move money, issue cards, and exchange currency, with built-in documentation search and safety confirmations for money-moving operations.

Enables AI agents to create and manage sellable listings, handle orders, and integrate Stripe payments through natural language using ListBee's API.

MCP server that gates API calls to AI agents using proof-of-work (free) or Lightning payment (3 sats), providing challenge, verify, and status tools for per-call authentication without accounts.

A budget-bound x402 payment wallet for AI agents: it autonomously pays HTTP 402 payment-gated URLs across every major chain (EVM, Solana, and many non-EVM families). Self-custodial and backendless, your key, your RPC, with spend caps enforced before any on-chain send.

Enables AI coding assistants to log billable hours into the Keeping time-tracking service via MCP tools, with dry-run protection for all write operations.

MCP server for real FDM 3D-printing slicing, quoting, and design-for-manufacturability analysis via the FabTally API, supporting 12 printer profiles and 12 materials. Includes free discovery/printability tools and paid slice/quote/orientation tools settled via x402 (USDC on Base).