Pay-per-call MCP tools over x402 (USDC on Base) — drop-in for SK agents

[naxytra (naxytra)]

For folks wiring MCP tools into Semantic Kernel: a public MCP endpoint where each tool call is settled with a micro-payment instead of an API key, so there's nothing to provision or store.

Endpoint: https://xytara-mcp-executor.onrender.com/mcp. tools/list is free; an unpaid tools/call returns a payment-required result with the price ($0.01 USDC; fetch-style x402 clients get HTTP 402 at /mcp/http402), the agent signs one gasless USDC authorization (x402 / EIP-3009), the Coinbase CDP facilitator settles it on Base mainnet only after the call succeeds, and the result comes back with an on-chain settlement receipt and a signed delivery receipt — a clean audit trail for enterprise agent runs.

17 deterministic tools (data/text utilities + EVM helpers like keccak256, abi.encode, eip712.hash), plus a paid lane for cryptographic proof verification including post-quantum (Ed25519 + ML-DSA-65). Autonomous, no human approval step.

More at https://naxytra.com/agents.