**Session Date/Time:** 21 Mar 2025 06:00

# sml

## Summary

The session focused on discussing potential additions and refinements to the SML (Structured Mail) draft, specifically concerning vacation notices for services, mailbox status information, and general improvements to structured data representation. Key topics included the complexity of modeling multiple periods of absence, the implications of vacation notices for services versus individuals, and ways to handle scenarios where a mailbox is permanently unavailable.  The base spec document was also reviewed.

## Key Discussion Points

*   **Multiple Periods of Absence:** The group agreed that modeling multiple periods of absence introduces unnecessary complexity and is not currently a priority for the draft.
*   **Vacation Notices for Services:**  The discussion centered around how to adapt vacation notices for services (e.g., legal entities, automated systems).  Two key suggestions were considered:
    *   **Generic Replacement Entities:**  Instead of just a replacement *person*, allow a replacement *entity*, using schema.org person or organization types. This enables services to provide more detailed contact information for alternatives (e.g., a doctor on duty).
    *   **Opening Hours:** Include schema.org's opening hours notation in structured vacation notices to indicate service availability within specific time frames.
*   **Time Zone Information:**  The need to include time zone information within the opening hours schema was raised, particularly for situations where recipients are in different time zones than the sender.
*   **Feature Creep:** Concerns were voiced about introducing excessive complexity, particularly with intraday availability, arguing that SML should primarily address scenarios of unavailability of more than one day.
*   **Mailbox Status Information:**  The discussion addressed cases where mailboxes are permanently unavailable, such as when a person leaves a company.  A proposal was made to add an "unavailability type" property to the structured vacation notice, with possible values like "temporary absence," "permanent unavailability," "no reply," or "moved."
*   **No-Reply Addresses:**  The session considered the use of SML to formalize the semantics of no-reply addresses, suggesting that a preemptive SML annotation could instruct email clients not to prompt users to reply.
*   **IANA Registry for Vocabularies:** There was support for creating an IANA registry for SML-related vocabularies, especially for those not covered by schema.org. Discussion covered whether the registry should provide resolvable identifiers and how to document vocabularies defined by the working group.
*   **Handling of MIME Structure:** The discussion covered what a client should do when it encounters a malformed email, particularly if it is supposed to be fully machine readable.
*   **Compatibility Testing:**  The results of compatibility tests with various email clients were presented, showing how structured data affects the rendering of emails in legacy clients. Most clients ignore the structured data, though some render it as an attachment. Encouraging clients to respect `content-disposition: inline` was proposed.
*   **Human readable email, AI Overlords**: Should text HTML be needed at all in emails?
*   **Trust**: There were discussions about a separate draft on trust of structured data and structured emails.
*   **Email signature**:  There was discussion about what to do when the email is sent from a company and the structure data does not include an email signature.
*   **NY Times**: There was discussions about how to provide structure data alongside an HTML email.
*   **Flights, AI Overlords**: The discussion asked if the email allows someone to respond with a structure data saying the flight is confirmed.
*   **Supersedes Header:**  The group considered using the `Supersedes` header to indicate that a previous structured data representation is no longer relevant (e.g., due to a flight rescheduling).

## Decisions and Action Items

*   **Additions to Draft:**
    *   Add a section to the draft discussing vacation notices for services, including the possibility of using schema.org person/organization types as replacement entities and incorporating the schema.org opening hours notation.
    *   Add a property to structured vacation notices indicating the "unavailability type" (temporary, permanent, no-reply, etc.).
*   **Additions to Draft (base spec)**
    *   Clarify `content-disposition`
    *   Make use of supersedes header
    *   Should text HTML be needed at all in emails?
*   **Action Items:**
    *   **Hans York:** Investigate further how content ID references and fragments within JSON-LD can be used in the context of SML.
    *   **Hans York:** Clarify the mime tree in the test results and provide a summary on the mailing list.
    *   **Hans York:** Investigate hosting options for IANA registry document.
    *   **Michael Richardson:** Start a draft for cases when `content-disposition` is not handled properly.
    *   **Hans York:** Send out a separate mailing list email on legal requirements on email signature.
    *   **Hans York**: Try to implement, try the supersede and see what happens.
*   **Review and Feedback:**
    *   Post the updated draft to the mailing list and specifically request feedback on the proposed additions related to vacation notices for services and mailbox status information.
    *   Bring the concerns raised about potential URL stripping and blocking by email clients to the mailing list for further discussion.

## Next Steps

*   Hans York will update the SML draft with the agreed-upon additions and changes.
*   The updated draft will be circulated on the mailing list for broader review and feedback.
*   The working group will continue to monitor and discuss the IANA registry options and potential integration.
*   The mailing list will be used to discuss the integration of NY Times use cases into the draft.