generated: '2026-09-19'
method: searched
source: https://scvd.store/try
docs:
- https://scvd.store/agents.md
- https://scvd.store/api/trade/contract
- https://scvd.store/api/conformance/v1/fixtures
- https://scvd.store/.well-known/conformance/offer-receipt-vectors.json
probed:
- {url: 'https://scvd.store/api/buy/small_blessing?src=apievangelist', method: GET, status: 402, fetched: '2026-09-19', note: 'unpaid; the real challenge, no test mode'}
- {url: 'https://scvd.store/api/preflight/v2', method: POST, body: '{}', status: 400, fetched: '2026-09-19', note: 'validation refusal; no probe spent, no RateLimit headers'}
- {url: 'https://scvd.store/try', status: 200}
- {url: 'https://scvd.store/.well-known/conformance/offer-receipt-vectors.json', status: 200, bytes: 14608}
summary: >-
  There is no test mode, no sandbox network and no test key — the provider says so on /try ("No test mode.
  The same code path serves everyone, which is what makes it worth testing against") and the OpenAPI's
  x402 accepts name only mainnet rails. What it publishes instead is a REAL-money practice counter with a
  floor of $0.001 (spot_check) / $0.005 (small_blessing), a free payment dry run for any x402 door, a trade
  counter sandbox account whose HMAC secret is deliberately public, published conformance fixtures and
  vectors with real production signatures, and a suggested Idempotency-Key in every 402 so a test harness
  cannot double-charge. Every value below is copied from the provider's pages; nothing is invented.
test_vs_live:
  separate_environment: false
  test_networks: none — 'wrong-network' (a testnet rail in accepts) is one of the 31 defect classes the store's own preflight flags on other doors
  key_prefixes: not applicable (no keys exist)
  note: '"The store is a live x402 target. Real settlement, no sandbox, no test mode, no separate code path." (skill.md)'
practice_counter:
  url: https://scvd.store/try
  cheapest_settlement: {item_id: small_blessing, price_usdc: 0.005, buy: 'https://scvd.store/api/buy/small_blessing?src=try', note: 'Half a cent, no arguments needed; ends in a signed certificate with a stable verify URL.'}
  cheapest_door: {item_id: spot_check, price_usdc: 0.001}
  deterministic_check: {item_id: daily_fortune, price_usdc: 0.01, note: '"returns the same line to every buyer until midnight UTC with fortune_date beside it — the one purchase whose answer you can check against another buyer''s."'}
  hello: {item_id: hello, price_usdc: 0.5, example: 'GET /api/buy/hello?agent_name=your-agent', note: 'Proves wallet, signing and retry path against a real counterparty.'}
  worked_example: https://scvd.store/try#hand-rolling (a hand-rolled EIP-712 payment "including the domain trap that fails silently")
  safe_retry: 'Echo the 402 body''s idempotency.suggested_key as Idempotency-Key with the payment; a second attempt inside the same minute returns the ORIGINAL purchase from cache — no settlement, no second charge.'
dry_runs:
- {operation: post_api_before_you_pay_v1, mcp_tool: check_before_you_pay, cli: 'scvd before-you-pay <url> [--cap <usd>]', description: 'Will a stock x402 client pay that door, and which accept would it sign? Nothing is signed, nothing is paid.'}
- {operation: 'any /api/buy/{item} without payment', description: 'Asking the price is free; required_params, input_contract_url, payload_template and amount_check come back without charge.'}
- {operation: get_api_practice_scenario, description: '"The obstacle course" — practice scenarios at /api/practice/{scenario}, some answering 402.'}
trade_counter_sandbox:
  account: sandbox
  key: scvd-trade-sandbox-key
  secret: scvd-trade-sandbox-secret-anyone-may-use
  note: 'Published in the trade contract on purpose ("whose secret is published") so any marketplace can exercise the HMAC dialect before an account exists. Not a credential to anything real.'
  check_desk: {operation: post_api_trade_sandbox_check, url: 'https://scvd.store/api/trade/sandbox/check', description: 'Send the headers and body you would send to the order door; every one of the four signature checks is reported by name plus the signature we expected. Nothing delivered, nothing consumed.'}
  order_door: {operation: post_api_trade_sandbox_item_id, url: 'https://scvd.store/api/trade/sandbox/{item_id}', description: 'Order one item on the sandbox account; settled_via reads trade_account_test.'}
  dialect: {headers: [X-Trade-Key, X-Trade-Timestamp, X-Trade-Nonce, X-Trade-Signature], signing_string: timestamp.nonce.body, signature: 'sha256=<lowercase hex HMAC-SHA256(secret, signing_string)>', timestamp: unix seconds, nonce: '^[0-9a-f]{32}$', window_seconds: 300}
  worked_signers: Node and Python examples in /api/trade/contract how_to_call.signers
fixtures:
- {name: conformance desk fixtures, operation: get_api_conformance_v1_fixtures, url: 'https://scvd.store/api/conformance/v1/fixtures', description: 'Complete artifacts with real production signatures (valid, expired, tampered, unknown-signer), the exact canonical string each covers, and the verdict the desk returns for each; re-verified against the live desk on every serve. "Building and testing against us costs nothing."'}
- {name: offer/receipt conformance vectors, url: 'https://scvd.store/.well-known/conformance/offer-receipt-vectors.json', description: 'Known-good and known-bad JWS artifacts, deterministic and regenerable from a published seed, including the algorithm-confusion case.'}
- {name: recorded 402 fixtures, url: 'https://scvd.store/fixtures.json', description: 'Recorded 402 doors, MPP challenges and signed-artifact vectors the store tests its own instruments against, with sha256 of the bytes served.'}
- {name: sample deliveries, url_template: 'https://scvd.store/samples/{item}.json', example: 'https://scvd.store/samples/small-blessing.json', description: 'A free delivery_outline specimen per item (sample_url in every 402 body).'}
- {name: live sample artifact, id: cert_4dww28dx5j, url: 'https://scvd.store/api/verify/cert_4dww28dx5j'}
client_ceiling:
  note: 'The stock @x402/core client applies a default $1 per-payment ceiling BEFORE picking an accept; 14 of 35 doors sit above it. Raise maxAmountPerPayment or pass spendControls: false deliberately — "It is your operator''s safety control and we ship nothing to route around it."'