"A search for a string containing SQL injection and XSS payload characters" matching MCP servers:

Open-source sample MCP server built to be audited: ships a paid-tool x402 demo, a deliberately scannable surface, and documented security posture. From Payload, makers of the MCP Launch Readiness Audit (48-rule scanner with a fix for every finding, hardening templates, stress-test harness, readiness verifier, CI workflow, branded audit report) and the MCP Monetization Kit.

Lets AI agents register, post job specs to matching specialist bots, authorize PayPal escrow funds, and capture payment only for units that pass acceptance checks. Covers the full job lifecycle — bidding, hashed contracts, funding, delivery verification, payouts, dispute mediation and long-polled events.

Universal HTTP 402 Micropayment Protocol & Autonomous Economic Settlement Engine for AI Agents on Base L2.

Pay-per-use semantic web search for AI agents. Powered by SearxNG, agents pay in sats via Lightning Network micropayments — no API keys 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.

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.

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

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-*.

Daily market-regime context for trading agents: is the market risk-on or risk-off? Free tools: rules, schema, ledger of issue hashes, 7-day-delayed issues, full PAPER results record (losses included), disclosures. Paid tool: today's issue via x402, 0.10 USDC on Base, with spend caps and optional Agent Trust payment preflight. No track record; not investment advice.

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.

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.

A locally runnable stdio MCP server for Fortrip hotel search, live room rates, hotel details, trip planning and booking payment links. Uses a Fortrip CLI token or saved CLI login; payments are completed by the user on Fortrip and Stripe.

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.

A shopper’s agent searches stores, compares prices and buys with the shopper’s approval.

A paid MCP server that lets AI agents send SMS messages to US phone numbers via x402 micropayments, with automatic compliance and opt-out handling.

PayCheck is an MCP server that checks a planned payment before an agent pays.

Keyless crypto payments for AI agents. One MCP call turns any wallet address into a non-custodial crypto payment link or tip jar, no API key and no account, with funds settling straight to your wallet at a 0% platform fee (USDC/USDT, BTC, LTC, DASH, DOGE, ZCASH).