The stamp

6.1 Shape

<stamp block="…" kind="…" [payload attributes…]>
  [optional child elements]
  A sentence a human would have typed.
</stamp>

• Attributes are the truth. Parse those.
• The body is the courtesy.
• One tag per block; several answered blocks means several tags, in touch order.
• The client writes it. The agent never does.

Named <stamp> and not <input>: <input> collides with a real HTML element, which a renderer or a model could plausibly confuse.

6.2 Per block

<!-- @choice select=one -->
<stamp block="project-kind" kind="choice" value="product" label="Product UI">
It is a product UI.
</stamp>

<!-- @choice / @gallery select=many -->
<stamp block="mood" kind="gallery" values="ed,br" labels="Editorial,Brutal">
I picked Editorial and Brutal.
</stamp>

<!-- @input -- note the masked secret -->
<stamp block="company" kind="input">
  <field name="legal">Acme Ltd</field>
  <field name="token">••••••</field>
I filled in the company details.
</stamp>

<!-- @upload -- files are ALSO attached to this turn as real parts -->
<stamp block="assets" kind="upload" count="2">
  <file name="brandbook.pdf" mime="application/pdf" size="2451920" pages="48" ref="blob_7f3ac91"/>
  <file name="logo.svg" mime="image/svg+xml" size="14204" ref="blob_c02de5"/>
I uploaded the brand book and the logo.
</stamp>

<!-- @link -->
<stamp block="refs" kind="link" count="1">
  <url href="https://example.com" fetched="yes" title="Example" desc="…"/>
These are the ones.
</stamp>

<!-- @scale -->
<stamp block="tone" kind="scale" steps="5">
  <dial name="formal" value="2" norm="0.25" poles="Formal|Playful"/>
</stamp>

<!-- @order -->
<stamp block="priorities" kind="order" values="craft,speed,cost">
Craft, then speed, then cost.
</stamp>

<!-- @card ask= -- value is the task REF, because that is the stable handle -->
<stamp block="ANV-114" kind="card" value="ANV-120" label="Runbook entry">
Pick up the runbook entry next.
</stamp>

<!-- @message ask= -- the send gate. The stamp says APPROVED, never `sent`. -->
<stamp block="intro-mail" kind="message" channel="email" value="send" state="approved" at="14:04:20" by="Ana">
Yes, send it.
</stamp>
<stamp block="intro-mail" kind="message" channel="email" value="hold" state="declined">
Not yet.
</stamp>

<!-- the outcome, written by the HOST afterwards. Not a second stamp. -->
<sent block="intro-mail" state="sent" at="14:04:23"/>
<sent block="intro-mail" state="failed" at="14:04:23" error="550 mailbox unavailable"/>

<!-- @connect -- one stamp, written when the consent screen ANSWERS. The
     refused scopes are named: an agent that reads only `state` will try to
     write to a Drive it was denied write access to. -->
<stamp block="gdrive" kind="connect" state="connected" provider="google-drive"
       values="drive.readonly,drive.metadata" labels="Read your files,See file names"
       at="14:02" by="Jonas">
I connected Google Drive.
</stamp>
<stamp block="gdrive" kind="connect" state="partial" provider="google-drive"
       values="drive.readonly,drive.metadata" refused="drive.file" at="14:02" by="Jonas">
I connected Google Drive, but not with write access.
</stamp>
<stamp block="gdrive" kind="connect" state="declined" provider="google-drive">
I would rather not connect that.
</stamp>

<!-- skipped / expired -->
<stamp block="refs" kind="link" skipped="yes">Skipped that one.</stamp>
<stamp block="mood" kind="gallery" expired="yes">That one timed out.</stamp>

A card stamps its task ref, never the label: the ref is what survives somebody rewording a subtask. A message stamps send or hold and nothing else — the body is already in the transcript above it, and repeating it in the tag gives an escaping bug somewhere to live.

The stamp never says sent. It says approved, because that is the only thing the click proves (§4.15.5). The outcome arrives afterwards as a separate <sent> tag written by the host, once, terminally. An agent that writes state="sent" is claiming a delivery it did not witness.

Every tag may also carry at= and, where more than one human can act, by=. Always include label/labels alongside value/values — whoever summarises this conversation later will not remember what br meant.

Use one serializer for all of this. One escaping policy, one place to fix it when a label contains a quote. Every block hand-rolling its own tag is a future escaping bug.

6.3 It renders as the stamp, not as a bubble

The tag is a real user turn in the model’s context. In the UI it renders as the stamped block, and nowhere else. A duplicate “you chose Editorial” bubble is noise, and worse, it separates the answer from the question it answered.

6.4 Free text still works

The composer never goes away. A human who ignores a block and types prose has answered it. Design every block so that “never answered” is survivable — most of them will not be. That is what @void is for.