diff --git a/CHANGELOG.md b/CHANGELOG.md
index e9a7402..d358f4e 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -2,6 +2,9 @@
 
 ## [Unreleased]
 
+- 💄 — Use a custom User-Agent header
+- 🐛 — Fix mail and gotify alerting
+
 ## 0.4.0
 
 Date: 2024-09-04
diff --git a/argos/agent.py b/argos/agent.py
index e0a4608..580553d 100644
--- a/argos/agent.py
+++ b/argos/agent.py
@@ -11,6 +11,7 @@ from typing import List
 import httpx
 from tenacity import retry, wait_random  # type: ignore
 
+from argos import VERSION
 from argos.checks import get_registered_check
 from argos.logging import logger
 from argos.schemas import AgentResult, SerializableException, Task
@@ -47,6 +48,8 @@ class ArgosAgent:
     async def run(self):
         headers = {
             "Authorization": f"Bearer {self.auth}",
+            "User-Agent": f"Argos Panoptes {VERSION} "
+            "(about: https://argos-monitoring.framasoft.org/)",
         }
         self._http_client = httpx.AsyncClient(headers=headers)
         logger.info("Running agent against %s", self.server)
diff --git a/argos/server/alerting.py b/argos/server/alerting.py
index 64e6bc9..60384aa 100644
--- a/argos/server/alerting.py
+++ b/argos/server/alerting.py
@@ -1,5 +1,6 @@
 import ssl
 import smtplib
+from email.message import EmailMessage
 
 from typing import List
 from urllib.parse import urlparse
@@ -107,10 +108,10 @@ See result on {request.url_for('get_result_view', result_id=result.id)}
 See results of task on {request.url_for('get_task_results_view', task_id=task.id)}#{result.id}
 """
 
-    mail = f"""\
-Subject: [Argos] {icon} {urlparse(task.url).netloc}: status {severity}
-
-{msg}"""
+    mail = EmailMessage()
+    mail["Subject"] = f"[Argos] {icon} {urlparse(task.url).netloc}: status {severity}"
+    mail["From"] = config.mailfrom
+    mail.set_content(msg)
 
     if config.ssl:
         logger.debug("Mail notification: SSL")
@@ -133,7 +134,7 @@ Subject: [Argos] {icon} {urlparse(task.url).netloc}: status {severity}
     for address in config.addresses:
         logger.debug("Sending mail to %s", address)
         logger.debug(msg)
-        smtp.sendmail(config.mailfrom, address, mail)
+        smtp.send_message(mail, to_addrs=address)
 
 
 def notify_with_gotify(
@@ -166,14 +167,16 @@ See results of task on <{request.url_for('get_task_results_view', task_id=task.i
     extras = {
         "client::display": {"contentType": "text/markdown"},
         "client::notification": {
-            "click": {"url": request.url_for("get_result_view", result_id=result.id)}
+            "click": {
+                "url": f"{request.url_for('get_result_view', result_id=result.id)}"
+            }
         },
     }
 
     payload = {"title": subject, "message": msg, "priority": priority, "extras": extras}
 
     for url in config:
-        logger.debug("Sending gotify message(s) to %s", url)
+        logger.debug("Sending gotify message(s) to %s", url.url)
         for token in url.tokens:
             try:
                 res = httpx.post(