1.23.0

• Key and credit purchases are paid in USDC only. insumer_buy_key, insumer_buy_credits and insumer_buy_merchant_credits take chainId 1, 10, 56, 137, 8453, 42161, 43114 or "solana"; "bitcoin" and "tron" are no longer accepted, and the API refuses USDT and any other token. Receiving addresses: 0xee432065474D2C852700f74e3fD81e2Bcc16a3D4 for USDC on Ethereum, Optimism, Polygon, Base, Arbitrum and Avalanche; 0xAd982CB19aCCa2923Df8F687C0614a7700255a23 for USDC on BNB Chain, which also accepts USDC on the other EVM chains during the changeover; 8fyEGM5tRjMocKQWaVXyM2XvvnTxR3sWdrYtug2zeLX4 for USDC on Solana, with 6a1mLjefhvSJX1sEX8PTnionbE9DqoYjU6F6bNkT4Ydr also accepted during the changeover. No Bitcoin or Tron address. amount is required on all three tools.
• New senderSignature input. The wallet that sent the payment signs a fixed five-line text naming the payment (domain, purpose, chain, transaction), with personal_sign on EVM (ERC-1271 for smart wallets) or signMessage on Solana. Required on every key purchase; on a credit purchase only when the key has no registered wallet yet, or with updateWallet: true from a different wallet. A call without it, when it is required, returns the exact text in a 400. The tool descriptions, README and SKILL.md state the text, the formats and the 403 and 503 cases.
• Unchanged: x402 pay-per-call, the hosted tool set (no hosted tool's name, description or schema changes), insumer_confirm_payment, and the chains the API reads, Bitcoin and Tron included.