Check whether your emails land in the inbox at Gmail and Outlook

import base64
import time
import uuid
from google.oauth2.credentials import Credentials
from googleapiclient.discovery import build
from clickruntime import on_trigger, http, credentials, notify

api = lambda name, version: build(name, version, credentials=Credentials(credentials.connection("google", "work")), cache_discovery=False)

def send_gmail(to, subject, text):
    raw = base64.urlsafe_b64encode(f"To: {to}\r\nSubject: {subject}\r\nContent-Type: text/plain; charset=utf-8\r\n\r\n{text}".encode()).decode()
    api("gmail", "v1").users().messages().send(userId="me", body={"raw": raw}).execute()

def graph(method, path, **kw):
    r = http.request(method, "https://graph.microsoft.com/v1.0" + path, headers={"Authorization": f"Bearer {credentials.connection('microsoft', 'work')}"}, **kw)
    return r.raise_for_status() or (r.json() if r.content else None)

def send_mail(to, subject, text):
    graph("POST", "/me/sendMail", json={"message": {"subject": subject, "body": {"contentType": "Text", "content": text},
          "toRecipients": [{"emailAddress": {"address": a}} for a in to.split(",")]}})

GMAIL_ADDR, OUTLOOK_ADDR = "you@northwind.example", "you@acme.example"

@on_trigger
def run(event):
    code = uuid.uuid4().hex[:8]
    send_gmail(OUTLOOK_ADDR, f"Deliverability test {code}", "Weekly test, safe to ignore.")
    send_mail(GMAIL_ADDR, f"Deliverability test {code}", "Weekly test, safe to ignore.")
    time.sleep(240)
    report = []
    for folder in ("inbox", "junkemail"):
        hits = graph("GET", f"/me/mailFolders/{folder}/messages", params={"$search": f'"{code}"', "$select": "internetMessageHeaders"})["value"]
        if hits:
            auth = next((h["value"] for h in hits[0].get("internetMessageHeaders", []) if h["name"].lower() == "authentication-results"), "")
            report.append(f"Gmail → Outlook: {'inbox' if folder == 'inbox' else 'JUNK'}; {auth[:300]}")
    gm = api("gmail", "v1").users().messages()
    found = gm.list(userId="me", q=f"{code} in:anywhere", includeSpamTrash=True).execute().get("messages", [])
    if found:
        m = gm.get(userId="me", id=found[0]["id"], format="metadata", metadataHeaders=["Authentication-Results"]).execute()
        auth = next((h["value"] for h in m["payload"]["headers"]), "")
        report.append(f"Outlook → Gmail: {'SPAM' if 'SPAM' in m['labelIds'] else 'inbox'}; {auth[:300]}")
    notify.email_me(f"Deliverability check {code}", "\n\n".join(report) or "Neither test email arrived within 4 minutes.")
    return {"results": len(report)}