{"data":{"provider":"exa","query":"x402 payment protocol HTTP 402","query_sha256":"9e0fb05be25f021acb7c3b84fc8c81ff87031b8d2b6405863483d50443238ba0","results":[{"rank":1,"title":"x402","url":"https://x402.org/","snippet":"image_animation=”none” border_type=”simple” column_border_width=”none” column_border_color=”#000000″ column_border_style=”solid” column_padding_type=”default” content_layout=”default” gradient_type=”default”][vc_column_text text_direction=”","highlights":["image_animation=”none” border_type=”simple” column_border_width=”none” column_border_color=”#000000″ column_border_style=”solid” column_padding_type=”default” content_layout=”default” gradient_type=”default”][vc_column_text text_direction=”"],"published_date":null,"snippet_sha256":"6ef3bbd706ed12c9c7f716debd19eaeda1083bef185c37ab17de39cd6b0e35af"},{"rank":2,"title":"","url":"https://docs.cdp.coinbase.com/x402/core-concepts/how-it-works","snippet":"x402 enables programmatic payments over ... 2. **Server responds with 402** - The resource server returns an HTTP 402 Payment Required status code with payment requirements in the `PAYMENT-REQUIRED` header. ... **Client creates payment** - The client examines the payment requirements and creates a payment payload using their wallet based on the specified scheme.","highlights":["x402 enables programmatic payments over ... 2. **Server responds with 402** - The resource server returns an HTTP 402 Payment Required status code with payment requirements in the `PAYMENT-REQUIRED` header. ... **Client creates payment** - The client examines the payment requirements and creates a payment payload using their wallet based on the specified scheme."],"published_date":null,"snippet_sha256":"df9e834edb5b289527f7e9fb933fbd806e27cabfdbea1c77771ab650ef468989"},{"rank":3,"title":"x402-foundation/x402","url":"https://github.com/x402-foundation/x402/","snippet":"1. `Client` makes an HTTP request to a `resource server`. ... . 3. `Client` selects one of the `PaymentRequirements` returned by the server response and creates a ... . 4. `Client` sends the HTTP request with the `PAYMENT-SIGNATURE` header containing the","highlights":["1. `Client` makes an HTTP request to a `resource server`. ... . 3. `Client` selects one of the `PaymentRequirements` returned by the server response and creates a ... . 4. `Client` sends the HTTP request with the `PAYMENT-SIGNATURE` header containing the"],"published_date":null,"snippet_sha256":"30d81dfd1ec231a08618c8203ef6c5e401687fe8508102909c7fdf1bfb7c09a8"},{"rank":4,"title":"HTTP 402","url":"https://docs.x402.org/core-concepts/http-402","snippet":"### What is HTTP 402? HTTP 402 is a standard, but rarely used, HTTP response status code indicating that payment is required to access a resource. In x402, this status code is activated to: - Inform clients (buyers or agents) that payment is required. - Communicate the details of the payment, such as amount, currency, and destination address. - Provide the information necessary to complete the payment programmatically. ... ### Payment Headers in V2 x402 V2 uses three standardized headers for payment communication: | Header | Direction | Description | | --- | --- | --- | | `PAYMENT-REQUIRED` | Server → Client | Base64-encoded `PaymentRequired` object | | `PAYMENT-SIGNATURE` | Client → Server | Base64-encoded `PaymentPayload` object | | `PAYMENT-RESPONSE` | Server → Client | Base64-encoded `SettlementResponse` object | - `PAYMENT-REQUIRED`: Contains the Base64-encoded payment requirements from the server. This header is returned alongside the 402 status code and includes details such as accepted payment schemes, price, network, and destination address. - `PAYMENT-SIGNATURE`: Contains the Base64-encoded payment payload from the client. This header is sent by the client when retrying a request after receiving a 402 response, proving they have authorized payment. - `PAYMENT-RESPONSE`: Contains the Base64-encoded settlement response from the server. This header is returned by the server after attempting settlement, whether successful or failed, providing structured feedback about the payment outcome. All headers contain valid Base64-encoded JSON strings. This encoding ensures compatibility across different HTTP implementations and prevents issues with special characters in JSON payloads.","highlights":["### What is HTTP 402? HTTP 402 is a standard, but rarely used, HTTP response status code indicating that payment is required to access a resource. In x402, this status code is activated to: - Inform clients (buyers or agents) that payment is required. - Communicate the details of the payment, such as amount, currency, and destination address. - Provide the information necessary to complete the payment programmatically. ... ### Payment Headers in V2 x402 V2 uses three standardized headers for payment communication: | Header | Direction | Description | | --- | --- | --- | | `PAYMENT-REQUIRED` | Server → Client | Base64-encoded `PaymentRequired` object | | `PAYMENT-SIGNATURE` | Client → Server | Base64-encoded `PaymentPayload` object | | `PAYMENT-RESPONSE` | Server → Client | Base64-encoded `SettlementResponse` object | - `PAYMENT-REQUIRED`: Contains the Base64-encoded payment requirements from the server. This header is returned alongside the 402 status code and includes details such as accepted payment schemes, price, network, and destination address. - `PAYMENT-SIGNATURE`: Contains the Base64-encoded payment payload from the client. This header is sent by the client when retrying a request after receiving a 402 response, proving they have authorized payment. - `PAYMENT-RESPONSE`: Contains the Base64-encoded settlement response from the server. This header is returned by the server after attempting settlement, whether successful or failed, providing structured feedback about the payment outcome. All headers contain valid Base64-encoded JSON strings. This encoding ensures compatibility across different HTTP implementations and prevents issues with special characters in JSON payloads."],"published_date":null,"snippet_sha256":"21c71cd2b1ad780315f55fdd32652c9be42b2359fa57e253f39afc7fdd5babee"},{"rank":5,"title":"How x402 works - Coinbase Developer Documentation","url":"https://docs.cdp.coinbase.com/x402/how-it-works","snippet":"x402 is an open standard for adding per-request payments to HTTP, so APIs and services can charge without checkout pages, subscriptions, or separate billing integrations. Payment becomes a client-server handshake: the server quotes a price in its","highlights":["x402 is an open standard for adding per-request payments to HTTP, so APIs and services can charge without checkout pages, subscriptions, or separate billing integrations. Payment becomes a client-server handshake: the server quotes a price in its"],"published_date":null,"snippet_sha256":"9def9cc1c45b9ee7d96875622d61fd16e720514cb16b1175f49cbe6afafd6b19"}],"result_count":5,"fetched_at":"2026-11-06T17:57:04.325Z","limits":{"note":"Ranking and snippets are the provider's at fetched_at; pages themselves are not fetched (use page-contents for that). published_date is the provider's value and may be null. 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