curl --request POST \
--url https://api.superx.so/v1/contacts/{id}/notes \
--header 'Authorization: Bearer <token>' \
--header 'Content-Type: application/json' \
--data '
{
"body": "Met at the SaaS meetup. Wants a demo in September."
}
'import requests
url = "https://api.superx.so/v1/contacts/{id}/notes"
payload = { "body": "Met at the SaaS meetup. Wants a demo in September." }
headers = {
"Authorization": "Bearer <token>",
"Content-Type": "application/json"
}
response = requests.post(url, json=payload, headers=headers)
print(response.text)const options = {
method: 'POST',
headers: {Authorization: 'Bearer <token>', 'Content-Type': 'application/json'},
body: JSON.stringify({body: JSON.stringify('Met at the SaaS meetup. Wants a demo in September.')})
};
fetch('https://api.superx.so/v1/contacts/{id}/notes', 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.superx.so/v1/contacts/{id}/notes",
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([
'body' => 'Met at the SaaS meetup. Wants a demo in September.'
]),
CURLOPT_HTTPHEADER => [
"Authorization: Bearer <token>",
"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.superx.so/v1/contacts/{id}/notes"
payload := strings.NewReader("{\n \"body\": \"Met at the SaaS meetup. Wants a demo in September.\"\n}")
req, _ := http.NewRequest("POST", url, payload)
req.Header.Add("Authorization", "Bearer <token>")
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.superx.so/v1/contacts/{id}/notes")
.header("Authorization", "Bearer <token>")
.header("Content-Type", "application/json")
.body("{\n \"body\": \"Met at the SaaS meetup. Wants a demo in September.\"\n}")
.asString();require 'uri'
require 'net/http'
url = URI("https://api.superx.so/v1/contacts/{id}/notes")
http = Net::HTTP.new(url.host, url.port)
http.use_ssl = true
request = Net::HTTP::Post.new(url)
request["Authorization"] = 'Bearer <token>'
request["Content-Type"] = 'application/json'
request.body = "{\n \"body\": \"Met at the SaaS meetup. Wants a demo in September.\"\n}"
response = http.request(request)
puts response.read_body{
"data": {
"id": "n1a2b3c4d5e6f7g8h9i0j",
"body": "Met at the SaaS meetup. Wants a demo in September.",
"created_at": "2026-09-06T10:00:00.000Z",
"updated_at": "2026-09-06T10:00:00.000Z",
"created_by": {
"x_user_id": "44196397",
"username": "yourhandle"
}
}
}{
"error": {
"code": "invalid_parameter",
"message": "since must be a UTC ISO-8601 timestamp"
}
}{
"error": {
"code": "invalid_api_key",
"message": "Unknown or revoked API key"
}
}{
"error": {
"code": "insufficient_scope",
"message": "This API key is read-only. Create a key with the write scope to use this endpoint."
}
}{
"error": {
"code": "contact_not_found",
"message": "No contact with that id belongs to this account. Contacts are the account's engagers, contact-list members and signal leads."
}
}{
"error": {
"code": "rate_limited",
"message": "Rate limit exceeded for the Pro plan (30 requests/min). Upgrade for higher limits.",
"retry_after": 42
}
}{
"error": {
"code": "upstream_error",
"message": "Failed to fetch scheduled posts. Try again shortly."
}
}{
"error": {
"code": "upstream_unavailable",
"message": "The scheduling service is temporarily unavailable. Retry with the same Idempotency-Key."
}
}Add a note to a contact
Write a private note about one person. The note is attributed to the
account it was written as (created_by), which for an API write is the
account named by account_id (your main account when omitted).
Creating a note requires a KNOWN contact: the id must be one of the
account’s engagers, contact-list members or signal leads, so an id
outside that set returns 404 contact_not_found. This is the only
note operation with that restriction - reading, editing and deleting
work on any id the account already has a note on.
No Idempotency-Key: notes have no uniqueness constraint, so a replay
creates a second note. Duplicates are visible in the list read and
deletable. Works for your main account or any account linked to it;
accounts shared with you are read-only. Needs the write scope.
curl --request POST \
--url https://api.superx.so/v1/contacts/{id}/notes \
--header 'Authorization: Bearer <token>' \
--header 'Content-Type: application/json' \
--data '
{
"body": "Met at the SaaS meetup. Wants a demo in September."
}
'import requests
url = "https://api.superx.so/v1/contacts/{id}/notes"
payload = { "body": "Met at the SaaS meetup. Wants a demo in September." }
headers = {
"Authorization": "Bearer <token>",
"Content-Type": "application/json"
}
response = requests.post(url, json=payload, headers=headers)
print(response.text)const options = {
method: 'POST',
headers: {Authorization: 'Bearer <token>', 'Content-Type': 'application/json'},
body: JSON.stringify({body: JSON.stringify('Met at the SaaS meetup. Wants a demo in September.')})
};
fetch('https://api.superx.so/v1/contacts/{id}/notes', 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.superx.so/v1/contacts/{id}/notes",
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([
'body' => 'Met at the SaaS meetup. Wants a demo in September.'
]),
CURLOPT_HTTPHEADER => [
"Authorization: Bearer <token>",
"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.superx.so/v1/contacts/{id}/notes"
payload := strings.NewReader("{\n \"body\": \"Met at the SaaS meetup. Wants a demo in September.\"\n}")
req, _ := http.NewRequest("POST", url, payload)
req.Header.Add("Authorization", "Bearer <token>")
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.superx.so/v1/contacts/{id}/notes")
.header("Authorization", "Bearer <token>")
.header("Content-Type", "application/json")
.body("{\n \"body\": \"Met at the SaaS meetup. Wants a demo in September.\"\n}")
.asString();require 'uri'
require 'net/http'
url = URI("https://api.superx.so/v1/contacts/{id}/notes")
http = Net::HTTP.new(url.host, url.port)
http.use_ssl = true
request = Net::HTTP::Post.new(url)
request["Authorization"] = 'Bearer <token>'
request["Content-Type"] = 'application/json'
request.body = "{\n \"body\": \"Met at the SaaS meetup. Wants a demo in September.\"\n}"
response = http.request(request)
puts response.read_body{
"data": {
"id": "n1a2b3c4d5e6f7g8h9i0j",
"body": "Met at the SaaS meetup. Wants a demo in September.",
"created_at": "2026-09-06T10:00:00.000Z",
"updated_at": "2026-09-06T10:00:00.000Z",
"created_by": {
"x_user_id": "44196397",
"username": "yourhandle"
}
}
}{
"error": {
"code": "invalid_parameter",
"message": "since must be a UTC ISO-8601 timestamp"
}
}{
"error": {
"code": "invalid_api_key",
"message": "Unknown or revoked API key"
}
}{
"error": {
"code": "insufficient_scope",
"message": "This API key is read-only. Create a key with the write scope to use this endpoint."
}
}{
"error": {
"code": "contact_not_found",
"message": "No contact with that id belongs to this account. Contacts are the account's engagers, contact-list members and signal leads."
}
}{
"error": {
"code": "rate_limited",
"message": "Rate limit exceeded for the Pro plan (30 requests/min). Upgrade for higher limits.",
"retry_after": 42
}
}{
"error": {
"code": "upstream_error",
"message": "Failed to fetch scheduled posts. Try again shortly."
}
}{
"error": {
"code": "upstream_unavailable",
"message": "The scheduling service is temporarily unavailable. Retry with the same Idempotency-Key."
}
}Authorizations
A SuperX API key ("sxk_..."), created in the SuperX app under Account > API / MCP / CLI. Keys are server-side secrets.
Path Parameters
The person's numeric X user id.
Body
Response
The created note.
A private note about one person. Notes live inside SuperX and are never posted.
Show child attributes
Show child attributes