docs: document scheduled sending with send_at parameter

[fern-api]

Adds a "Scheduled sending" section to the Sending & Receiving Email guide, documenting how to use the send_at parameter when creating a Draft to schedule emails for future delivery.

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Summary by cubic

Add a “Scheduled sending” section to the Sending & Receiving Email guide, showing how to schedule emails by setting the send_at parameter on Drafts. Includes Python/TypeScript examples, status tracking via send_status, and steps to cancel or reschedule.

^{Written for commit c996ebb. Summary will update on new commits.}

[github-actions]

🌿 Preview your docs: https://agentmail-preview-9541cae0-3f00-4a91-bd53-19048c052cf1.docs.buildwithfern.com

[cubic-dev-ai]

1 issue found across 1 file

Prompt for AI agents (unresolved issues)

Check if these issues are valid — if so, understand the root cause of each and fix them. If appropriate, use sub-agents to investigate and fix each issue separately.


<file name="fern/pages/guides/sending-receiving-email.mdx">

<violation number="1" location="fern/pages/guides/sending-receiving-email.mdx:45">
P2: The Python scheduled-send example uses a timezone-naive `datetime` while documenting UTC, which can schedule at the wrong time if interpreted in local/default timezone. Use an explicitly UTC timestamp.</violation>
</file>

_{Reply with feedback, questions, or to request a fix. Tag @cubic-dev-ai to re-run a review.}

[cubic-dev-ai]

P2: The Python scheduled-send example uses a timezone-naive datetime while documenting UTC, which can schedule at the wrong time if interpreted in local/default timezone. Use an explicitly UTC timestamp.

Prompt for AI agents

Check if this issue is valid — if so, understand the root cause and fix it. At fern/pages/guides/sending-receiving-email.mdx, line 45:

<comment>The Python scheduled-send example uses a timezone-naive `datetime` while documenting UTC, which can schedule at the wrong time if interpreted in local/default timezone. Use an explicitly UTC timestamp.</comment>

<file context>
@@ -25,6 +25,47 @@ client.inboxes.messages.send(
+    subject="Quick question about your garden",
+    text="Hi, I wanted to follow up on the seedling order.",
+    html="<p>Hi, I wanted to follow up on the seedling order.</p>",
+    send_at=datetime(2026, 3, 5, 9, 0, 0),
+)
+
</file context>

Suggested change

	send_at=datetime(2026, 3, 5, 9, 0, 0),
	send_at=datetime.fromisoformat("2026-03-05T09:00:00+00:00"),