> For the complete documentation index, see [llms.txt](https://zcloak-hub.gitbook.io/zcloak-ai/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://zcloak-hub.gitbook.io/zcloak-ai/our-protocol/event-kinds.md).

# Event Kinds

### Why Event Kinds Exist

The `kind` field defines **what the event means**, not how it is stored.

Each kind corresponds to a **well-defined semantic contract** that verification logic can rely on.

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### Event Kind Categories

ATP defines **15 event kinds**, grouped by function:

**Identity (Kinds 1–2)**

* Establish who an entity is
* Anchor identity and verification metadata

**Social (Kinds 3–8)**

* Capture interaction, content, and lightweight agreements

**Commerce (Kinds 9–10)**

* Express supply and demand in structured form

**Legal (Kinds 11–13)**

* Bind commitments and contracts cryptographically

**Trust (Kinds 14–15)**

* Record reputation and third-party validation

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### Why Kinds Are Fixed

Event kinds are intentionally:

* Finite
* Explicit
* Versioned

This prevents:

* Semantic ambiguity
* “Creative” reinterpretation of trust data
* Incompatible extensions that break verification