[core] Browse the hou-tea Chinese tea catalog. Returns products with name, price (USD/USDC), images, taste profile, fermentation level, season, and a ready-to-render card object.

[core] Get curated tea recommendations from a natural-language query. Returns ranked products with explanation. Best entry point when the user asks 'recommend me a tea for X' or describes a mood / occasion / use-case.

[core] Returns origin story, brewing guide (water temp, steep time, ratio), health benefits, talking points, cultural context, and cross-sell suggestions for one product.

[core] Initiate an x402 USDC payment intent for a product. Returns HTTP 402-style payment requirements (recipient address, amount, Base chain network). Auto-includes buyer order grouping (register_buyer_list_token or env HOU_TEA_BUYER_LIST_TOKEN). The wallet MCP MUST POST the identical buy_request_body on retry plus header X-Payment.

[core] Poll the status of a previously created order. Status transitions: pending_payment → verifying → confirmed (after on-chain USDC settlement). Use exponential backoff (~2s, 4s, 8s …, max ~60s).

[core] List USDC/x402 orders associated with the buyer_list_token (returned from a successful purchase or stored in env HOU_TEA_BUYER_LIST_TOKEN). No merchant API key required.

[meta] Reveal extended tools (compare / health-filter / agent-card) by adding them to tools/list. Optionally filter by groups or specific tools. Call this when the core 6 tools aren't enough for the user's intent. Idempotent.