Send magic link
Public, cart-token–scoped. Sends a magic-link / MFA challenge to the
customer’s email and returns a challenge uuid (201) to submit to
POST …/auth/verify. No bearer token is required. fluid_shop here is the
company subdomain (e.g. acme). Set lookup_only: true for a
returning-buyer probe that only looks up an existing customer and never
creates one — a 404 then signals the frontend to treat the email as a
guest and skip confirmation. Returns 410 when the cart is a
locked/authorized enrollment cart and 422 on validation errors.
curl --request POST \
--url https://api.fluid.app/api/checkout/v2026-04/carts/{cart_token}/auth/magic_link \
--header 'Content-Type: application/json' \
--data '
{
"email": "customer@example.com",
"fluid_shop": "acme"
}
'import requests
url = "https://api.fluid.app/api/checkout/v2026-04/carts/{cart_token}/auth/magic_link"
payload = {
"email": "customer@example.com",
"fluid_shop": "acme"
}
headers = {"Content-Type": "application/json"}
response = requests.post(url, json=payload, headers=headers)
print(response.text)const options = {
method: 'POST',
headers: {'Content-Type': 'application/json'},
body: JSON.stringify({email: 'customer@example.com', fluid_shop: 'acme'})
};
fetch('https://api.fluid.app/api/checkout/v2026-04/carts/{cart_token}/auth/magic_link', options)
.then(res => res.json())
.then(res => console.log(res))
.catch(err => console.error(err));<?php
$curl = curl_init();
curl_setopt_array($curl, [
CURLOPT_URL => "https://api.fluid.app/api/checkout/v2026-04/carts/{cart_token}/auth/magic_link",
CURLOPT_RETURNTRANSFER => true,
CURLOPT_ENCODING => "",
CURLOPT_MAXREDIRS => 10,
CURLOPT_TIMEOUT => 30,
CURLOPT_HTTP_VERSION => CURL_HTTP_VERSION_1_1,
CURLOPT_CUSTOMREQUEST => "POST",
CURLOPT_POSTFIELDS => json_encode([
'email' => 'customer@example.com',
'fluid_shop' => 'acme'
]),
CURLOPT_HTTPHEADER => [
"Content-Type: application/json"
],
]);
$response = curl_exec($curl);
$err = curl_error($curl);
curl_close($curl);
if ($err) {
echo "cURL Error #:" . $err;
} else {
echo $response;
}package main
import (
"fmt"
"strings"
"net/http"
"io"
)
func main() {
url := "https://api.fluid.app/api/checkout/v2026-04/carts/{cart_token}/auth/magic_link"
payload := strings.NewReader("{\n \"email\": \"customer@example.com\",\n \"fluid_shop\": \"acme\"\n}")
req, _ := http.NewRequest("POST", url, payload)
req.Header.Add("Content-Type", "application/json")
res, _ := http.DefaultClient.Do(req)
defer res.Body.Close()
body, _ := io.ReadAll(res.Body)
fmt.Println(string(body))
}HttpResponse<String> response = Unirest.post("https://api.fluid.app/api/checkout/v2026-04/carts/{cart_token}/auth/magic_link")
.header("Content-Type", "application/json")
.body("{\n \"email\": \"customer@example.com\",\n \"fluid_shop\": \"acme\"\n}")
.asString();require 'uri'
require 'net/http'
url = URI("https://api.fluid.app/api/checkout/v2026-04/carts/{cart_token}/auth/magic_link")
http = Net::HTTP.new(url.host, url.port)
http.use_ssl = true
request = Net::HTTP::Post.new(url)
request["Content-Type"] = 'application/json'
request.body = "{\n \"email\": \"customer@example.com\",\n \"fluid_shop\": \"acme\"\n}"
response = http.request(request)
puts response.read_body{
"meta": {
"request_id": "<string>",
"timestamp": "2023-11-07T05:31:56Z"
},
"multi_factor_authentication": {
"authenticated": true,
"uuid": "<string>",
"verification_channel": "<string>",
"verification_code_expires_at": "2023-11-07T05:31:56Z"
}
}{
"error_message": "<string>",
"errors": "<string>",
"meta": {
"request_id": "<string>",
"timestamp": "2023-11-07T05:31:56Z"
}
}{
"error_message": "<string>",
"errors": "<string>",
"meta": {
"request_id": "<string>",
"timestamp": "2023-11-07T05:31:56Z",
"shop_url": "<string>",
"cart": "<unknown>"
}
}{
"error_message": "<string>",
"errors": "<string>",
"meta": {
"request_id": "<string>",
"timestamp": "2023-11-07T05:31:56Z"
}
}Path Parameters
Cart token
Body
Customer email to send magic link to
"customer@example.com"
Company subdomain
"acme"
Returning-buyer probe. When true, only looks up an existing customer and never creates one; a not-found (404) tells the frontend to treat the email as a guest and skip the confirmation step.
curl --request POST \
--url https://api.fluid.app/api/checkout/v2026-04/carts/{cart_token}/auth/magic_link \
--header 'Content-Type: application/json' \
--data '
{
"email": "customer@example.com",
"fluid_shop": "acme"
}
'import requests
url = "https://api.fluid.app/api/checkout/v2026-04/carts/{cart_token}/auth/magic_link"
payload = {
"email": "customer@example.com",
"fluid_shop": "acme"
}
headers = {"Content-Type": "application/json"}
response = requests.post(url, json=payload, headers=headers)
print(response.text)const options = {
method: 'POST',
headers: {'Content-Type': 'application/json'},
body: JSON.stringify({email: 'customer@example.com', fluid_shop: 'acme'})
};
fetch('https://api.fluid.app/api/checkout/v2026-04/carts/{cart_token}/auth/magic_link', options)
.then(res => res.json())
.then(res => console.log(res))
.catch(err => console.error(err));<?php
$curl = curl_init();
curl_setopt_array($curl, [
CURLOPT_URL => "https://api.fluid.app/api/checkout/v2026-04/carts/{cart_token}/auth/magic_link",
CURLOPT_RETURNTRANSFER => true,
CURLOPT_ENCODING => "",
CURLOPT_MAXREDIRS => 10,
CURLOPT_TIMEOUT => 30,
CURLOPT_HTTP_VERSION => CURL_HTTP_VERSION_1_1,
CURLOPT_CUSTOMREQUEST => "POST",
CURLOPT_POSTFIELDS => json_encode([
'email' => 'customer@example.com',
'fluid_shop' => 'acme'
]),
CURLOPT_HTTPHEADER => [
"Content-Type: application/json"
],
]);
$response = curl_exec($curl);
$err = curl_error($curl);
curl_close($curl);
if ($err) {
echo "cURL Error #:" . $err;
} else {
echo $response;
}package main
import (
"fmt"
"strings"
"net/http"
"io"
)
func main() {
url := "https://api.fluid.app/api/checkout/v2026-04/carts/{cart_token}/auth/magic_link"
payload := strings.NewReader("{\n \"email\": \"customer@example.com\",\n \"fluid_shop\": \"acme\"\n}")
req, _ := http.NewRequest("POST", url, payload)
req.Header.Add("Content-Type", "application/json")
res, _ := http.DefaultClient.Do(req)
defer res.Body.Close()
body, _ := io.ReadAll(res.Body)
fmt.Println(string(body))
}HttpResponse<String> response = Unirest.post("https://api.fluid.app/api/checkout/v2026-04/carts/{cart_token}/auth/magic_link")
.header("Content-Type", "application/json")
.body("{\n \"email\": \"customer@example.com\",\n \"fluid_shop\": \"acme\"\n}")
.asString();require 'uri'
require 'net/http'
url = URI("https://api.fluid.app/api/checkout/v2026-04/carts/{cart_token}/auth/magic_link")
http = Net::HTTP.new(url.host, url.port)
http.use_ssl = true
request = Net::HTTP::Post.new(url)
request["Content-Type"] = 'application/json'
request.body = "{\n \"email\": \"customer@example.com\",\n \"fluid_shop\": \"acme\"\n}"
response = http.request(request)
puts response.read_body{
"meta": {
"request_id": "<string>",
"timestamp": "2023-11-07T05:31:56Z"
},
"multi_factor_authentication": {
"authenticated": true,
"uuid": "<string>",
"verification_channel": "<string>",
"verification_code_expires_at": "2023-11-07T05:31:56Z"
}
}{
"error_message": "<string>",
"errors": "<string>",
"meta": {
"request_id": "<string>",
"timestamp": "2023-11-07T05:31:56Z"
}
}{
"error_message": "<string>",
"errors": "<string>",
"meta": {
"request_id": "<string>",
"timestamp": "2023-11-07T05:31:56Z",
"shop_url": "<string>",
"cart": "<unknown>"
}
}{
"error_message": "<string>",
"errors": "<string>",
"meta": {
"request_id": "<string>",
"timestamp": "2023-11-07T05:31:56Z"
}
}