Guides · Tag
foundations
10 guides tagged foundations.
Email for Agents · Sep 30, 2026
Does ChatGPT Have an Email Address?
No. ChatGPT has no address of its own, but it can act inside your Gmail or Outlook. What OpenAI documents today, and what owning an inbox takes.
Inboxes · Sep 30, 2026
Thread ID vs Message-ID in an Agent Inbox
Agent email thread ID vs message ID vs the Message-ID header: which to store, which a counterparty can forge, and what reply_to_message_id accepts.
Email for Agents · Sep 27, 2026
Two AI Agents Emailing Each Other: A Design Guide
Two AI agents emailing each other rarely stop on their own: why courtesy keeps the thread alive, how threading works, when to hand off, how to test it.
Inboxes · Sep 26, 2026
How Many Tokens an Email Thread Really Costs
How many tokens does an email thread use? We built a 10-message thread and counted: 4% was new text. Here is the retrieval pattern that fixes it.
Email for Agents · Sep 26, 2026
An Email Address Is an Agent's First Identity
AI agent identity starts with an email address. What a mailbox proves, what DKIM and DMARC never check, and what A2A, OAuth and AP2 still leave to email.
Email for Agents · Sep 26, 2026
State of Agent Email 2026: Four Architectures
Agent email architecture types, tested against 20 products' own docs: what each is best at, and the failures each will keep no matter who builds it.
Developers · Sep 22, 2026
Is a mail.invalid Test Email Address Safe?
Why a mail.invalid test email address is safe: the .invalid TLD can never resolve, so a misrouted test send is unsendable rather than merely intercepted.
Inboxes · Sep 21, 2026
AI Agent Inbox vs Connecting Gmail: How to Choose
Giving an agent its own inbox versus wiring it into an existing Gmail or Microsoft 365 mailbox: identity, blast radius, OAuth scope and revocation.
Email for Agents · Sep 21, 2026
Email for AI Agents: How Agent Inboxes Actually Work
What an email inbox for an AI agent is, how mail arrives and leaves, which permissions matter, and when an agent needs its own address instead of yours.
Developers · Sep 21, 2026
Keep an Agent's Replies in the Right Email Thread
How Message-ID, In-Reply-To and References decide threading, why subject matching breaks, and how to keep an agent reply in the right conversation.