Message

Message media Primitive

Chat message row — media + author/time meta + bubble. Outbound rows reverse with data-from=out.

Layer: L1 surface · Recipe: unset — see docs/agent/pick-a-surface.md. Curriculum: AGENTS.md; pick matrix: docs/agent/pick-a-surface.md; blast radius: CONSUMER_MAP.md.

Maya Reyes

Can we reschedule the walkthrough to Thursday?

You

Thursday 14:00 works — I'll send a calendar hold.

Copy this

html
<div class="hm-stack" style="gap:0.75rem;max-width:28rem">
  <div class="message" data-message data-from="in">
    <span class="message__media" aria-hidden="true">MR</span>
    <div class="message__body">
      <div class="message__meta"><span class="message__author">Maya Reyes</span><time class="message__time" datetime="2026-07-12T10:02">10:02</time></div>
      <div class="bubble" data-bubble data-from="in">
        <p>Can we reschedule the walkthrough to Thursday?</p>
      </div>
    </div>
  </div>
  <div class="message" data-message data-from="out">
    <span class="message__media" aria-hidden="true">You</span>
    <div class="message__body">
      <div class="message__meta"><span class="message__author">You</span><time class="message__time" datetime="2026-07-12T10:04">10:04</time></div>
      <div class="bubble" data-bubble data-from="out">
        <p>Thursday 14:00 works — I'll send a calendar hold.</p>
      </div>
    </div>
  </div>
</div>

Server exchange

This Hyperpart has no server exchange — it is presentation or client chrome only. htmx does not issue a request on this part's behalf. If you put an affordance (hx-*) on a control that uses this markup, that action's exchange belongs to the action, not this part. See Swap contract for host-owned envelopes.

Swap contract

Agent-visible HTMX topology (ADR-0054 / decision 0012). exchange envelope = what the response may re-emit relative to the persistent slot (body_only | outer | none | host_owned | document). dual-lock validates part markup only — not this envelope. Stem: stems/morph-safe-hypermedia.md; decision: docs/decisions/0012-swap-identity-contract.md.

No host HTMX exchange on this part — presentation or client chrome only. exchange envelope: n/a.

If a host wraps this markup in hx-*, that host owns the swap contract (sole identity + envelope). Prefer innerMorph / outerMorph for stable slots; replacement for flash; body-only responses under inner swaps.

Envelope response examples

This part has no owned exchange (envelope n/a). If a host adds hx-*, that host’s envelope applies — typically body_only:

html
<!-- Host wraps this presentation part with hx-* (host owns envelope) -->
<!-- Prefer: hx-swap="innerMorph" hx-target="#panel-body" -->
<!-- Server returns body_only interior for #panel-body -->
<div class="dz-stack">content…</div>

Do not re-own the slot:

html
<!-- WRONG: server returns the presentation root with a new id every poll -->
<div id="message-root" data-dz-region>…</div>

How to use it

No extended guidance authored yet — start from Copy this and the dependency chips (Primitive = markup only; controller = load listed JS; Endpoint = implement Server exchange).

Seams

  • copy the partial under Copy this; keep root class and data-* modifiers so the CSS/JS bundle matches
  • no Server exchange on this part — pure presentation or client chrome
  • satisfy the DOM contract tables (CI stop-ship)

DOM contract

What the emitted HTML must satisfy — the table is the required surface; Python under contracts/ is the package-internal dual-lock CI runs (tests/test_contracts.py), not an app route. Standalone HTMX4: implement the API so responses match this markup. Dazzle: the agent emits SSR that already satisfies it. Do not invent attrs outside these tables. For request/response wiring see Server exchange.

contracts/message.py

Required in the DOM: root .message (part message). Emit only these attributes — inventing extras is fine only if controllers ignore them; omitting required ones fails CI (tests/test_contracts.py).

NodeAttrConstraint
.message——

Module source

Import path is monorepo/package-local (from contracts._kit import …). Source-token form often uses data-*; gallery demos above are unprefixed. Do not copy this into app routes.

python
"""HYPERPART: message — chat message row (media + meta + bubble).

Dual-lock unit is the message root. Author/time, bubble body, and
``data-dz-from`` orientation are host-owned. Class ``.dz-message`` is the
stable substrate root (gallery CSS; Fragment ``Message`` +
``display: conversation`` emit the spine with nested ``Bubble``).
"""

from contracts._kit import DomContract, Node

DOM_CONTRACT = DomContract(
    part="message",
    root=".dz-message",
    nodes=(Node(".dz-message", attrs={}),),
)

__all__ = ["DOM_CONTRACT"]

Notes

PLACEHOLDER — shadcn parity (HMC-041). Composes bubble. Live chat = server re-render / OOB append into message-scroller, not client message state. Dual-lock root .message (HMC-134).

Source files

Canonical registration in the registry. No dedicated controller — CSS for this part lives in the layered bundle.

site/registry.py · contracts/message.py