Preview slots for a calendar definition
The slots a calendar would offer with the settings you send. Nothing is saved.
Send the whole definition under calendar. The settings are checked with the same rules as POST /api/native-calendar/calendars, so invalid hours are reported before saving.
Pass calendarId as well to preview a change to an existing calendar. Its current bookings are then counted.
A locationId inside calendar is ignored. The sub-account is the locationId parameter.
Required API key scope: projects:read.
POST
/
api
/
native-calendar
/
calendars
/
preview
cURL
curl --request POST \
--url https://api.teamfollowup.ai/api/native-calendar/calendars/preview \
--header 'Authorization: Bearer YOUR_API_KEY' \
--header 'Content-Type: application/json' \
--data '{
"calendarId": "cal_6b1f2a7c90",
"calendar": {
"timezone": "America/Chicago",
"weeklyHours": {
"mon": [
{
"start": "08:00",
"end": "18:00"
}
]
},
"slotDurationMinutes": 45,
"minNoticeMinutes": 60
}
}'import requests
url = "https://api.teamfollowup.ai/api/native-calendar/calendars/preview"
payload = { "calendar": {
"timezone": "America/Chicago",
"weeklyHours": { "mon": [
{
"start": "08:00",
"end": "18:00"
}
] },
"slotDurationMinutes": 45,
"minNoticeMinutes": 60
} }
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({
calendar: {
timezone: 'America/Chicago',
weeklyHours: {mon: [{start: '08:00', end: '18:00'}]},
slotDurationMinutes: 45,
minNoticeMinutes: 60
}
})
};
fetch('https://api.teamfollowup.ai/api/native-calendar/calendars/preview', 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.teamfollowup.ai/api/native-calendar/calendars/preview",
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([
'calendar' => [
'timezone' => 'America/Chicago',
'weeklyHours' => [
'mon' => [
[
'start' => '08:00',
'end' => '18:00'
]
]
],
'slotDurationMinutes' => 45,
'minNoticeMinutes' => 60
]
]),
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.teamfollowup.ai/api/native-calendar/calendars/preview"
payload := strings.NewReader("{\n \"calendar\": {\n \"timezone\": \"America/Chicago\",\n \"weeklyHours\": {\n \"mon\": [\n {\n \"start\": \"08:00\",\n \"end\": \"18:00\"\n }\n ]\n },\n \"slotDurationMinutes\": 45,\n \"minNoticeMinutes\": 60\n }\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.teamfollowup.ai/api/native-calendar/calendars/preview")
.header("Authorization", "Bearer <token>")
.header("Content-Type", "application/json")
.body("{\n \"calendar\": {\n \"timezone\": \"America/Chicago\",\n \"weeklyHours\": {\n \"mon\": [\n {\n \"start\": \"08:00\",\n \"end\": \"18:00\"\n }\n ]\n },\n \"slotDurationMinutes\": 45,\n \"minNoticeMinutes\": 60\n }\n}")
.asString();require 'uri'
require 'net/http'
url = URI("https://api.teamfollowup.ai/api/native-calendar/calendars/preview")
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 \"calendar\": {\n \"timezone\": \"America/Chicago\",\n \"weeklyHours\": {\n \"mon\": [\n {\n \"start\": \"08:00\",\n \"end\": \"18:00\"\n }\n ]\n },\n \"slotDurationMinutes\": 45,\n \"minNoticeMinutes\": 60\n }\n}"
response = http.request(request)
puts response.read_body{
"success": true,
"data": {
"timezone": "America/Chicago",
"slots": {
"2026-09-24": {
"slots": [
"2026-09-24T14:00:00.000Z",
"2026-09-24T14:30:00.000Z",
"2026-09-24T15:00:00.000Z"
]
},
"2026-09-25": {
"slots": [
"2026-09-25T14:00:00.000Z"
]
}
}
}
}{
"success": false,
"error": "BadRequest",
"message": "Something here doesn't look right. Please check it and try again."
}{
"success": false,
"error": "Unauthorized",
"message": "Please sign in to continue."
}{
"success": false,
"error": "Forbidden",
"message": "You don't have access to this. Ask your account admin if you need it."
}{
"success": false,
"error": "NotFound",
"message": "We couldn't find that. It may have been moved or deleted."
}{
"success": false,
"error": "TooManyRequests",
"message": "That's a lot at once. Please wait a moment and try again."
}{
"success": false,
"error": "Internal",
"message": "Something went wrong on our side. Please try again in a moment.",
"ref": "3f2b8c1e-7d4a-4f8e-9b6a-2c1d0e5f7a9b"
}{
"success": false,
"error": "ServiceUnavailable",
"message": "This isn't available right now. Please try again in a moment.",
"ref": "3f2b8c1e-7d4a-4f8e-9b6a-2c1d0e5f7a9b"
}Authorizations
Query Parameters
Body
application/json
The definition to try.
⌘I
cURL
curl --request POST \
--url https://api.teamfollowup.ai/api/native-calendar/calendars/preview \
--header 'Authorization: Bearer YOUR_API_KEY' \
--header 'Content-Type: application/json' \
--data '{
"calendarId": "cal_6b1f2a7c90",
"calendar": {
"timezone": "America/Chicago",
"weeklyHours": {
"mon": [
{
"start": "08:00",
"end": "18:00"
}
]
},
"slotDurationMinutes": 45,
"minNoticeMinutes": 60
}
}'import requests
url = "https://api.teamfollowup.ai/api/native-calendar/calendars/preview"
payload = { "calendar": {
"timezone": "America/Chicago",
"weeklyHours": { "mon": [
{
"start": "08:00",
"end": "18:00"
}
] },
"slotDurationMinutes": 45,
"minNoticeMinutes": 60
} }
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({
calendar: {
timezone: 'America/Chicago',
weeklyHours: {mon: [{start: '08:00', end: '18:00'}]},
slotDurationMinutes: 45,
minNoticeMinutes: 60
}
})
};
fetch('https://api.teamfollowup.ai/api/native-calendar/calendars/preview', 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.teamfollowup.ai/api/native-calendar/calendars/preview",
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([
'calendar' => [
'timezone' => 'America/Chicago',
'weeklyHours' => [
'mon' => [
[
'start' => '08:00',
'end' => '18:00'
]
]
],
'slotDurationMinutes' => 45,
'minNoticeMinutes' => 60
]
]),
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.teamfollowup.ai/api/native-calendar/calendars/preview"
payload := strings.NewReader("{\n \"calendar\": {\n \"timezone\": \"America/Chicago\",\n \"weeklyHours\": {\n \"mon\": [\n {\n \"start\": \"08:00\",\n \"end\": \"18:00\"\n }\n ]\n },\n \"slotDurationMinutes\": 45,\n \"minNoticeMinutes\": 60\n }\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.teamfollowup.ai/api/native-calendar/calendars/preview")
.header("Authorization", "Bearer <token>")
.header("Content-Type", "application/json")
.body("{\n \"calendar\": {\n \"timezone\": \"America/Chicago\",\n \"weeklyHours\": {\n \"mon\": [\n {\n \"start\": \"08:00\",\n \"end\": \"18:00\"\n }\n ]\n },\n \"slotDurationMinutes\": 45,\n \"minNoticeMinutes\": 60\n }\n}")
.asString();require 'uri'
require 'net/http'
url = URI("https://api.teamfollowup.ai/api/native-calendar/calendars/preview")
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 \"calendar\": {\n \"timezone\": \"America/Chicago\",\n \"weeklyHours\": {\n \"mon\": [\n {\n \"start\": \"08:00\",\n \"end\": \"18:00\"\n }\n ]\n },\n \"slotDurationMinutes\": 45,\n \"minNoticeMinutes\": 60\n }\n}"
response = http.request(request)
puts response.read_body{
"success": true,
"data": {
"timezone": "America/Chicago",
"slots": {
"2026-09-24": {
"slots": [
"2026-09-24T14:00:00.000Z",
"2026-09-24T14:30:00.000Z",
"2026-09-24T15:00:00.000Z"
]
},
"2026-09-25": {
"slots": [
"2026-09-25T14:00:00.000Z"
]
}
}
}
}{
"success": false,
"error": "BadRequest",
"message": "Something here doesn't look right. Please check it and try again."
}{
"success": false,
"error": "Unauthorized",
"message": "Please sign in to continue."
}{
"success": false,
"error": "Forbidden",
"message": "You don't have access to this. Ask your account admin if you need it."
}{
"success": false,
"error": "NotFound",
"message": "We couldn't find that. It may have been moved or deleted."
}{
"success": false,
"error": "TooManyRequests",
"message": "That's a lot at once. Please wait a moment and try again."
}{
"success": false,
"error": "Internal",
"message": "Something went wrong on our side. Please try again in a moment.",
"ref": "3f2b8c1e-7d4a-4f8e-9b6a-2c1d0e5f7a9b"
}{
"success": false,
"error": "ServiceUnavailable",
"message": "This isn't available right now. Please try again in a moment.",
"ref": "3f2b8c1e-7d4a-4f8e-9b6a-2c1d0e5f7a9b"
}