Deliverability

Every update we have filed under Deliverability. 5 entries and counting - newest first.

2026

28OCT 26

AI Agents Are Now Cold-Emailing at Scale: What the iLands Episode Means for Senders

In September 2026 autonomous AI agents on the iLands platform began cold-emailing researchers, freelancers and editors to sell small paid tasks, often around $20 to $25. One NYU professor counted about 40 emails in a week from different agent personas. iLands added an unsubscribe option and says it is reviewing rate limits, cross-agent deduplication and stop-contact controls. By late October the same agents were pitching newsrooms, with almost no takers. For senders the lesson is simple: an agent that emails strangers is a sender like any other, and the Gmail, Yahoo and Microsoft rules apply to it from the first message.

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ai-agentscold-emailbulk-senderunsubscribe

9OCT 26

DeliverabilityMedium impact

APRF Adopted by the IETF MAILMAINT Working Group: What Changed in the New Draft

APRF graduated from an individual submission to a working-group draft: the IETF MAILMAINT working group adopted it on 8 October 2026 and republished it as draft-ietf-mailmaint-aprf-00 on 9 October, replacing draft-brotman-aggregate-performance-reporting. The protocol barely changed - a new selector-less record form, an explicit record-discovery order and a corrected subject-prefix typo - so any APRF record already published keeps working unchanged. Comcast is still the only mailbox provider sending reports.

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aprfietf-draftmailmaintreporting

29SEP 26

DeliverabilityHigh impact

Validity Launches "Heatwave", a Blocklist Targeting Artificial Domain Warmup

On 3 September 2026 Validity launched Heatwave, a blocklist that targets synthetic (artificial) domain warming - services that spin up networks of fake mailboxes to fake opens, clicks and replies and manufacture sender reputation. It launched with 1M+ domains listed, is mirrored into Validity's DNS reputation zones, and is used or evaluated by Comcast, Proofpoint, Spamhaus and SURBL - so a listing can affect real delivery. Delisting is a manual review and stopping the warmup is not, on its own, grounds for removal.

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blocklistwarmupcold-emailvalidity

28SEP 26

DeliverabilityLow impact

AI Assistants Can Now Run Live Email-Deliverability Checks (via MCP)

AI assistants like Claude can now run real email-deliverability checks through MCP (the Model Context Protocol), an open standard for connecting tools to assistants. Anthropic's Connectors Directory now lists such tools, so a user can ask "is my domain blacklisted?" and the assistant runs the actual check on the tool's infrastructure rather than guessing from training data. Postbox Services is among the first email-deliverability tools listed.

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mcpai-assistantstooling

9AUG 26

DeliverabilityMedium impact

APRF: The Draft Standard That Would Finally Show Senders Where Their Mail Lands

An IETF draft - now draft-ietf-mailmaint-aprf, after the MAILMAINT working group adopted it in October 2026 - proposes a DMARC-style mechanism for mailbox providers to email senders daily JSON reports on inbox placement and engagement, keyed to the DKIM signing domain, not the From address. It is still early (Comcast is the only provider sending beta reports, with a Google engineer among the authors), but it could finally standardize the placement data that has always lived behind per-provider portals.

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aprfietf-draftreporting