"Information about voice or speech-related topics" matching MCP servers:

Enables AI agents to call paid APIs and settle HTTP 402 payment challenges with USDC on Base, without private keys ever being involved.

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).

Lets an AI agent hire and pay a verified human: post real-world tasks (voice, observation, judgment) and pay in USDC via a non-custodial x402 auth-capture escrow on Base, budget frozen at deploy. Humans verify their X identity before submitting.

MCP server that lets a chatbot browse eSIM plans, sign in, prepare quotes, and execute wallet or card purchases on an existing eSIM platform, with safe typed tools.

Universal x402 buyer agent — discover, pay for, and call any x402 paid API endpoint from Claude Desktop, Cursor, or Claude Code with automatic USDC payment via AgentCash.

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.

MCP Server for AI agents to discover and call pay-per-request APIs via EntRoute. Give Claude, Cursor, Windsurf, or any MCP-compatible agent access to 350+ verified x402 API endpoints across 110+ capabilities — DeFi prices, web search, prediction markets, news, and more.

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

A local MCP server that integrates ProofJSON to assess invoices before payment, providing allow/review/block decisions with confidence scores and verification capabilities.

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.

Enables AI agents to browse the giftcardshop catalog and purchase gift cards using Lightning payments, with no account or signup required.

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.

Connect Peil to Claude (or any MCP client): log hours, draft invoices from unbilled hours, and check where you stand — from a prompt.

Enables building client statements of account from existing invoices, credit notes, and deposits, with aged outstanding balances, PDF/plain-text output, and drafted payment chasers at friendly, firm, or final levels.

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

Enables AI assistants to access the Billingo v3 invoicing API through MCP, providing 49 read/write tools for managing invoices, partners, and related data over stdio or HTTP transports.