Pay with a wallet
Use an installed EVM wallet, or open Coinbase Wallet through a desktop QR code or mobile handoff.
API Acre verifies the exact x402 price, Base network, recipient, and request before any wallet opens. One successful call costs $0.008 USDC.
API Acre never receives your private key; signing stays inside your wallet.
Connecting opens Coinbase Wallet. It does not sign or pay.
Both routes use this exact verified request and one-call price. Nothing is connected, signed, installed, or paid until you continue.
Use an installed EVM wallet, or open Coinbase Wallet through a desktop QR code or mobile handoff.
Copy a command locked to this endpoint, request, and exact USDC cap. Copying is inert; running it may install the official CLI and pay after its authentication and policy checks.
The wallet did not connect, so nothing was signed or paid. Copy this same request and exact USDC cap for Coinbase Agentic Wallet; copying does not install or run it.
No ETH gas needed. Connecting does not sign or pay. This EIP-3009 payment needs only the displayed USDC on Base because the facilitator submits settlement. Reject any later prompt that differs from the verified amount or recipient.
Running this command may automatically spend up to $0.008 USDC. npx --yes approves package installation. Use a separate low-value wallet and review the verified request first.
npx --yes awal@latest x402 pay https://apiacre.com/v1/research/crossref-work-search \
-X POST \
-d '{"query":"agentic commerce payment protocols","max_results":5,"work_type":"journal-article","sort_by":"relevance"}' \
--max-amount 8000 \
--jsonThe first command checks without paying; running fetch may pay up to the same exact cap.
npx --yes agentcash@latest check https://apiacre.com/v1/research/crossref-work-search
npx --yes agentcash@latest fetch https://apiacre.com/v1/research/crossref-work-search \
--method POST \
--header 'content-type: application/json' \
--body '{"query":"agentic commerce payment protocols","max_results":5,"work_type":"journal-article","sort_by":"relevance"}' \
--payment-protocol x402 \
--payment-network base \
--max-amount 0.008Crossref scholarly work search returns structured JSON. This example is static; the paid call returns a fresh result and settlement receipt.
{
"request_id": "018f1f54-7f38-7ba2-8dc3-5f90272d9f1a",
"service": "research.crossref-work-search",
"version": "1",
"data": {
"query": {
"bibliographic": "agentic commerce payment protocols",
"workType": "journal-article",
"publishedFrom": null,
"publishedUntil": null,
"sortBy": "relevance"
},
"totalResults": 1,
"resultsReturned": 1,
"results": [
{
"doi": "10.1000/apiacre.example",
"title": "A bounded example scholarly work",
"type": "journal-article",
"publishedDate": "2026-08-20",
"authors": [
{
"name": "Ada Example",
"given": "Ada",
"family": "Example",
"orcid": null,
"affiliations": [
"Example Institute"
]
}
],
"publisher": "Example Publisher",
"containerTitle": "Agent Systems",
"subjects": [
"Software agents"
],
"language": "en",
"doiUrl": "https://doi.org/10.1000/apiacre.example",
"resourceUrl": "https://api.crossref.org/works/10.1000%2Fapiacre.example",
"referenceCount": 8,
"citedByCount": 12,
"issn": [
"0000-0000"
],
"isbn": [],
"licenses": [],
"updates": []
}
],
"source": "https://api.crossref.org/works",
"retrievedAt": "2026-08-20T12:00:00+00:00",
"documentation": "https://www.crossref.org/documentation/retrieve-metadata/rest-api/",
"metadataLicense": {
"name": "Open bibliographic metadata / Crossref-generated data CC0",
"url": "https://www.crossref.org/documentation/retrieve-metadata/",
"abstractsReturned": false
},
"limitations": [
"Demonstration metadata only; paid calls return current publisher-deposited records.",
"Abstracts and full text are deliberately excluded."
]
},
"meta": {
"duration_ms": 42,
"cached": false,
"sources": [],
"warnings": [],
"next_actions": [
{
"service": "research.crossref-doi-metadata",
"title": "Crossref DOI metadata enrichment",
"reason": "Resolve one selected scholarly-search candidate into a focused current DOI metadata record.",
"method": "POST",
"path": "/v1/research/crossref-doi-metadata",
"price": "$0.003",
"input_template": {
"doi": "$result.data.results[0].doi"
},
"use_output": "Continue only after selecting the intended result; inspect correction or update links and source limitations before relying on the record.",
"handoff_path": "/catalog/research.crossref-doi-metadata",
"checkout_path": "/try/research.crossref-doi-metadata",
"sample_path": "/samples/research.crossref-doi-metadata",
"maximum_atomic_usdc": "3000",
"handoff_payment_required": false,
"executes_automatically": false,
"authorization_required": true
}
]
}
}Checking the connected wallet's Base USDC balance without signing or paying.
Signing authorizes only the verified amount and recipient for this request. Reject the wallet prompt if anything differs. The displayed balance is read locally through your wallet provider and is never sent to API Acre.
The x402 Register independently checks API Acre's unpaid challenge, price, protocol version, and availability. It does not purchase or validate paid results.
Open the current report ↗The default request is verified automatically. Editing it invalidates the quote and requires this no-payment verification again.
Prefer your own client? Use the official x402 SDK examples. Browser checkout requires an EVM wallet with USDC on Base; command-line buyers require their own separately configured wallet and spending policy.