"Research assistant for AI and ML papers, code, and methodology" matching MCP servers:

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

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.

MCP server for Online Boutique AI Assistant that exposes 18 e-commerce microservice functions via the Model Context Protocol, enabling any MCP client to manage products, carts, checkout, payments, and shipping.

MCP server for creating and fiscalizing invoices via solo.com.hr API. Enables AI agents to generate invoices, retrieve invoice details, list invoices, and check next invoice number.

Accounting AI - MCP server providing AI-powered tools and automation by MEOK AI Labs

Enables AI agents to call Safaricom's M-Pesa Daraja API directly, sending STK push prompts, checking balances, looking up or reversing transactions, and receiving results as SUCCESS, FAILED, or UNKNOWN. Requests are sent once per idempotency key with sandbox-by-default operation, so agents can operate and test payments without risking double charges or real money.

Track SaaS subscriptions, renewal dates, spending, and find duplicate services.

Enables AI agents to browse, list, buy, review, and get paid for digital goods through MCP tools, including balance, ledger, checkout-link, upload, and payout operations. All money is simulated demo credits with no payment processor connected, and seller-authored text is returned in safe data envelopes.

Enables AI assistants to learn about a Fort Lauderdale corporate video studio, plan videos and draft scripts, send briefs and brand guidelines, find and book calls, and get deposit links for fixed quotes.

Enables agents and humans to pay per question over x402 and receive plain-language answers about on-chain activity, priced by complexity before execution. Each paid request runs a live subgraph round trip to search, validate, generate and execute a GraphQL query, then synthesizes the raw results into a grounded response alongside the underlying data.

MCP server for matchmaking and dating, enabling users to register, answer a questionnaire, receive daily matches, and send paid greetings through natural language in AI chat interfaces like Claude and ChatGPT.

AI Agent Hub is a pay-per-call API platform for AI agents Every call is billed automatically in USDC using the x402 protocol - there is no API key, no account, and no signup. Agents get instant access to data queries, file storage, and ad impressions, paying only for what they actually use. The same tools are also exposed natively over MCP, so any MCP-capable agent can discover and call them

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

Enables AI agents to browse product catalogs and make purchases through a policy engine that enforces spending limits, requires human approval for certain amounts, and logs all actions to an audit trail.

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-*.

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 MCP clients to discover and call pay-per-call hub agents as individual tools, with per-call USDC spending caps on Base, automatic x402 payment signing, and provenance verification.

Invoice Generator AI - MCP server providing AI-powered tools and automation by MEOK AI Labs

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.

Enables AI assistants to create and manage invoices, process sandbox payments and refunds, generate PDF receipts, and inspect transactions, subscriptions, disputes, and merchant insights through a unified tool gateway backed by PayPal Sandbox APIs.

Enables AI agents to use pay-per-call web-to-Markdown, structured extraction, crawling, Base token and wallet data, FX rates, and crypto alert tools via USDC payments on Base.

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.

Remote MCP server providing free tools for value-bearing responses and trust receipts, plus optional consent-based commerce, enabling agents and humans to connect to a coordinated AI operator.

Lets AI agents and developers list a catalog of troubleshooting datasets, preview up to three records per product for free, and get Lightning payment instructions to unlock full structured datasets.

MCP server that provides tools for retrieving transaction context and recording AI decisions or creating human reviews for payment risk exceptions. Enables LLM agents to handle exception transactions in a hybrid payment-decisioning workflow.

Automates Spectrum/Charter ISP account management tasks such as viewing account overview, paying bills, checking outages, and scheduling technician visits via browser automation.

Enables AI assistants to resolve CIMS parties, quote and send transfers, handle attestation, and track intent lifecycles on the Roots CIMS network, with built-in safety rails that refuse raw addresses and require confirmation before sending.

Enables users to retrieve BIN data for a given BIN number, with optional enhanced attributes for richer insights.

An MCP server that enables AI assistants to automate Cash App payments, balance checks, and transaction management via browser automation.