# The bit passport

> Proposal · not yet in the parser

The bit passport is one header at the top of a delivery that applies to every
bit in it: who holds the rights, under which licence, what AI may do with the
content, and which accessibility standard it meets. What describes a single
bit's content stays in that bit.

## What it carries

| In the passport, once per delivery | Stays in each bit |
| --- | --- |
| Rights: copyright, licence, rights policy, publisher | Identity: the bit's ID and the customer's ID |
| AI use: what agents may do (retrieve, quote, cite, train) | The AI label and the machine-translation label a reader must show |
| How the content was made: AI model, operation, human review | The language of a passage |
| Accessibility claim: conformance, certifier, features, hazards, summary | Accessibility evidence: alt text, decorative marks, table headers |
| Origin: source document, edition, translation of | Where the bit sits in the original |
| Audience, when it holds for every bit: language, age, level | |

A bit never overrides the passport's rights: narrowing the rights for a
single bit makes no sense. Content under other rights goes into a delivery of
its own, with its own passport.

## Shape on the wire

The passport is the first line of a JSONL delivery, under its own key, so a
reader tells it apart from the bits that follow. The names are drafts:

```json
{"passport": {"@context": ["https://schema.org"], "publisher": "Example Publisher", "license": "https://creativecommons.org/licenses/by/4.0/", "inLanguage": "en", "conformsTo": "EPUB Accessibility 1.1 - WCAG 2.2 Level AA", "aiUse": {"retrieve": true, "train": false}}}
{"bit": {"type": "p", "id": ["a1"], "body": "…"}}
{"bit": {"type": "p", "id": ["a2"], "aiGenerated": true, "aiDisclosureRequired": true, "body": "…"}}
```

The passport is planned as JSON-LD, so it can reuse vocabularies that exist
already instead of new names: schema.org for publisher, licence, language and
accessibility, and the W3C's policy and text-and-data-mining vocabularies for
what AI may do. Compact JSON-LD reads as plain JSON, so no linked-data tools
are needed. The bit lines stay plain JSON.

## The accessibility claim

The passport states the claim; the bits carry the evidence, so the claim can
be checked. It uses the terms EPUB Accessibility already defines, so an EPUB
export takes them over unchanged:

- conformance, for example "EPUB Accessibility 1.1 – WCAG 2.2 Level AA";
- who certified it, with their credential and report;
- the access modes and which of them suffice alone;
- the features present: alternative text, long descriptions, transcripts,
  captions, table of contents, reading order, structural navigation;
- hazards: none, flashing, motion or sound;
- a plain-language summary.

## Today

Until the passport ships, these properties are bit tags: `@copyright`,
`@license`, `@rightsPolicy`, `@publisher`, the AI tags such as `@aiGenerated`
and `@aiModel`, and the accessibility and audience tags. The reference lists
them on every bit page. The working groups of the bitmark Association each
own one section of the passport.