Start an x402 payment session
curl --request POST \
--url http://localhost:3773/api/start-payment-session \
--header 'Authorization: Bearer <token>'import requests
url = "http://localhost:3773/api/start-payment-session"
headers = {"Authorization": "Bearer <token>"}
response = requests.post(url, headers=headers)
print(response.text)const options = {method: 'POST', headers: {Authorization: 'Bearer <token>'}};
fetch('http://localhost:3773/api/start-payment-session', options)
.then(res => res.json())
.then(res => console.log(res))
.catch(err => console.error(err));<?php
$curl = curl_init();
curl_setopt_array($curl, [
CURLOPT_PORT => "3773",
CURLOPT_URL => "http://localhost:3773/api/start-payment-session",
CURLOPT_RETURNTRANSFER => true,
CURLOPT_ENCODING => "",
CURLOPT_MAXREDIRS => 10,
CURLOPT_TIMEOUT => 30,
CURLOPT_HTTP_VERSION => CURL_HTTP_VERSION_1_1,
CURLOPT_CUSTOMREQUEST => "POST",
CURLOPT_HTTPHEADER => [
"Authorization: Bearer <token>"
],
]);
$response = curl_exec($curl);
$err = curl_error($curl);
curl_close($curl);
if ($err) {
echo "cURL Error #:" . $err;
} else {
echo $response;
}package main
import (
"fmt"
"net/http"
"io"
)
func main() {
url := "http://localhost:3773/api/start-payment-session"
req, _ := http.NewRequest("POST", url, nil)
req.Header.Add("Authorization", "Bearer <token>")
res, _ := http.DefaultClient.Do(req)
defer res.Body.Close()
body, _ := io.ReadAll(res.Body)
fmt.Println(string(body))
}HttpResponse<String> response = Unirest.post("http://localhost:3773/api/start-payment-session")
.header("Authorization", "Bearer <token>")
.asString();require 'uri'
require 'net/http'
url = URI("http://localhost:3773/api/start-payment-session")
http = Net::HTTP.new(url.host, url.port)
request = Net::HTTP::Post.new(url)
request["Authorization"] = 'Bearer <token>'
response = http.request(request)
puts response.read_body{
"session_id": "ps_01H8...",
"status": "pending",
"amount": "0.01",
"asset": "USDC",
"network": "base-sepolia",
"pay_to": "0x2654bb8B272f117c514aAc3d4032B1795366BA5d",
"created_at": "2026-04-19T18:00:00+00:00",
"expires_at": "2026-04-19T18:05:00+00:00",
"capture_url": "https://agent.example.com/payment-capture?session_id=ps_01H8..."
}Payment (x402)
Start an x402 payment session
Initiates a payment session for agents that charge per
request. Returns a session handle the caller uses with
message/send (via the X-PAYMENT header or session-linked
metadata) until the session is spent or expired.
Paid agents only. Unpaid agents return 404.
POST
/
api
/
start-payment-session
Start an x402 payment session
curl --request POST \
--url http://localhost:3773/api/start-payment-session \
--header 'Authorization: Bearer <token>'import requests
url = "http://localhost:3773/api/start-payment-session"
headers = {"Authorization": "Bearer <token>"}
response = requests.post(url, headers=headers)
print(response.text)const options = {method: 'POST', headers: {Authorization: 'Bearer <token>'}};
fetch('http://localhost:3773/api/start-payment-session', options)
.then(res => res.json())
.then(res => console.log(res))
.catch(err => console.error(err));<?php
$curl = curl_init();
curl_setopt_array($curl, [
CURLOPT_PORT => "3773",
CURLOPT_URL => "http://localhost:3773/api/start-payment-session",
CURLOPT_RETURNTRANSFER => true,
CURLOPT_ENCODING => "",
CURLOPT_MAXREDIRS => 10,
CURLOPT_TIMEOUT => 30,
CURLOPT_HTTP_VERSION => CURL_HTTP_VERSION_1_1,
CURLOPT_CUSTOMREQUEST => "POST",
CURLOPT_HTTPHEADER => [
"Authorization: Bearer <token>"
],
]);
$response = curl_exec($curl);
$err = curl_error($curl);
curl_close($curl);
if ($err) {
echo "cURL Error #:" . $err;
} else {
echo $response;
}package main
import (
"fmt"
"net/http"
"io"
)
func main() {
url := "http://localhost:3773/api/start-payment-session"
req, _ := http.NewRequest("POST", url, nil)
req.Header.Add("Authorization", "Bearer <token>")
res, _ := http.DefaultClient.Do(req)
defer res.Body.Close()
body, _ := io.ReadAll(res.Body)
fmt.Println(string(body))
}HttpResponse<String> response = Unirest.post("http://localhost:3773/api/start-payment-session")
.header("Authorization", "Bearer <token>")
.asString();require 'uri'
require 'net/http'
url = URI("http://localhost:3773/api/start-payment-session")
http = Net::HTTP.new(url.host, url.port)
request = Net::HTTP::Post.new(url)
request["Authorization"] = 'Bearer <token>'
response = http.request(request)
puts response.read_body{
"session_id": "ps_01H8...",
"status": "pending",
"amount": "0.01",
"asset": "USDC",
"network": "base-sepolia",
"pay_to": "0x2654bb8B272f117c514aAc3d4032B1795366BA5d",
"created_at": "2026-04-19T18:00:00+00:00",
"expires_at": "2026-04-19T18:05:00+00:00",
"capture_url": "https://agent.example.com/payment-capture?session_id=ps_01H8..."
}Authorizations
bearerAuthdidSignature
OAuth2 access token issued by Ory Hydra. Required for most operations.
Scopes:
agent:read— Read-only operations (tasks/get, tasks/list, contexts/list)agent:write— Write operations (message/send, tasks/cancel, contexts/clear)agent:execute— (legacy) Both read and write access
How to obtain:
- Register your client with Hydra
- Complete OAuth2 client credentials or authorization code flow
- Include token in
Authorization: Bearer <token>header
Response
200 - application/json
Payment session opened
Available options:
pending, completed, failed, expired Amount as string to avoid float precision
Example:
"USDC"
Example:
"base-sepolia"
Wallet address to pay
Human-facing payment URL
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