docs: README + api_provider example show alias_amount_fields + x402_sample probe (parity with node)

Mirror of node-commerce 8881db4. README's payment + discovery rows mention
alias_amount_fields, sample_x402_accept_for_network, and x402_sample probe
option. examples/api_provider.py's probe call now uses X402SampleProbe with
the networks shorthand.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

Author: vvillait88

README.md

@@ -17,8 +17,8 @@ pip install agentscore-commerce[fastapi]   # or [flask], [django], [aiohttp], [s
 |---|---|
 | `agentscore_commerce.identity.{fastapi,flask,django,aiohttp,sanic,middleware}` | Trust gate middleware: KYC, sanctions, age, jurisdiction. `AgentScoreGate(...)` (or `agentscore_gate(app, ...)` on Flask/Sanic), `get_assess_data(...)`, `capture_wallet(...)`, `verify_wallet_signer_match(...)`. |
 | `agentscore_commerce.identity` (package level) | Re-exports the denial helpers: `denial_reason_status`, `denial_reason_to_body`, `build_signer_mismatch_body`, `build_contact_support_next_steps`, `verification_agent_instructions`, `is_fixable_denial`, `FIXABLE_DENIAL_REASONS`. |
-| `agentscore_commerce.payment` | `networks`, `USDC`, `rails` registries; `payment_directive`, `build_payment_directive`, `www_authenticate_header`, `payment_required_header`, `settlement_override_header`, `dispatch_settlement_by_network`, `extract_payment_signer` (returns `PaymentSigner({address, network})`), `register_x402_schemes_v1_v2`; drop-in x402 helpers: `validate_x402_network_config` (boot-time guard), `verify_x402_request` (parse + validate inbound X-Payment), `process_x402_settle` (verify-then-settle with one call). |
-| `agentscore_commerce.discovery` | `is_discovery_probe_request`, `build_discovery_probe_response`, `build_well_known_mpp`, `build_llms_txt` + `llms_txt_identity_section` + `llms_txt_payment_section` (compact + verbose modes), `agentscore_openapi_snippets`, `build_bazaar_discovery_payload`. |
+| `agentscore_commerce.payment` | `networks`, `USDC`, `rails` registries; `payment_directive`, `build_payment_directive`, `www_authenticate_header`, `payment_required_header`, `alias_amount_fields` (v1↔v2 amount field shim — emits both `amount` and `maxAmountRequired` so v1-only x402 parsers like Coinbase awal can read v2 bodies), `settlement_override_header`, `dispatch_settlement_by_network`, `extract_payment_signer` (returns `PaymentSigner({address, network})`), `register_x402_schemes_v1_v2`; drop-in x402 helpers: `validate_x402_network_config` (boot-time guard), `verify_x402_request` (parse + validate inbound X-Payment), `process_x402_settle` (verify-then-settle with one call). |
+| `agentscore_commerce.discovery` | `is_discovery_probe_request`, `build_discovery_probe_response` (with optional `x402_sample` for x402-aware crawlers — `awal x402 details` etc.), `sample_x402_accept_for_network` (USDC sample-accept builder for known CAIP-2 networks), `build_well_known_mpp`, `build_llms_txt` + `llms_txt_identity_section` + `llms_txt_payment_section` (compact + verbose modes), `agentscore_openapi_snippets`, `build_bazaar_discovery_payload`. |
 | `agentscore_commerce.challenge` | `build_402_body`, `build_accepted_methods`, `build_identity_metadata`, `build_how_to_pay`, `build_agent_instructions`; `respond_402` — drop-in 402 emit that preserves pympp's `WWW-Authenticate` and layers x402's `PAYMENT-REQUIRED`. |
 | `agentscore_commerce.stripe_multichain` | `create_multichain_payment_intent`, `get_deposit_address`, `simulate_crypto_deposit`; `create_pi_cache` (TTL'd PI / deposit-address cache, Redis-backed when `redis_url` set, in-memory otherwise), `simulate_deposit_if_test_mode` (gates on `sk_test_` and looks up the PI for you), `STRIPE_TEST_TX_HASH_SUCCESS` / `STRIPE_TEST_TX_HASH_FAILED` constants. Peer dep on `stripe`. |
 | `agentscore_commerce.api` | Everything from `agentscore-py` re-exported in one place: `AgentScore` + `AgentScoreError`, `AGENTSCORE_TEST_ADDRESSES` + `is_agentscore_test_address`. **Don't add `agentscore-py` as a separate dep** — the two can drift versions and cause subtle type mismatches. |

examples/api_provider.py

@@ -35,6 +35,7 @@
 
 from agentscore_commerce.discovery import (
     DiscoveryProbeOptions,
+    X402SampleProbe,
     build_discovery_probe_response,
     is_discovery_probe_request,
 )
@@ -67,6 +68,13 @@ async def search(request: Request):
                 sample_rail="tempo-mainnet",
                 sample_amount_usd=PRICE_USDC,
                 sample_recipient=os.environ["TEMPO_RECIPIENT"],
+                # Advertise x402 support so crawlers (e.g. ``awal x402 details``)
+                # can find it on an empty-body POST. Commerce synthesizes USDC
+                # sample accepts from the registry per CAIP-2 network passed.
+                x402_sample=X402SampleProbe(
+                    networks=[networks.base.mainnet.caip2, networks.solana.mainnet.caip2],
+                    resource_url=f"{REALM}/search",
+                ),
             )
         )
         return JSONResponse(json.loads(probe.body), status_code=probe.status, headers=probe.headers)