Open spec · 2026

An approach for working with HTML artifacts.

LLMs emit them by default. Agents return them. Chats render them. The format your tools already speak is the format your work should land in.

12rules
5required blocks
0network deps

The durable unit of knowledge is shifting from the note to the artifact.

So HTML is the substrate. Now what?

§ I. Four questions

Archive. Share. Fork. Export.

The things raw HTML artifacts don't answer on their own. Capsule is the discipline that makes them answer — by construction, not by hosting.

i. Archive

How do you archive it?

It's just a .html file. Save it anywhere — Dropbox, USB, GitHub, an inbox, a folder on disk. The manifest makes the file self-describing for a future reader.

no externals · core rule 02

ii. Share

How do you share it?

The bytes are the artifact. No host required, no link to expire, no platform to revoke access. Once it reaches a recipient, it's theirs.

cannot be unshared · core rule 10

iii. Fork

How do you fork it?

The manifest's parents[] field records lineage. Paste a capsule into a new LLM session; the next one it produces knows what it built on.

parents[] · manifest field

iv. Export

How do you get it out of your LLM?

Paste the produce prompt from the spec. Out comes a sealed .html you can save — not a link inside the chat, not a hosted artifact you depend on, just bytes you control.

produce prompt · CAPSULE_CORE.md

About this capsule · exports · manifest

This page is itself a Capsule per Core v0.3.0 (full spec v0.3.2). Five required blocks, all inline. No network, no analytics. Validates against the reference validator.

Manifest

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