# Core concepts

> Documentation index: [llms.min.txt](https://caseyrfsmith.github.io/scull/llms.min.txt) · Document manifest: [documents.json](https://caseyrfsmith.github.io/scull/documents.json)

Breadcrumbs: Build and use > Core concepts

| Term        | Meaning                                                           |
| ----------- | ----------------------------------------------------------------- |
| Docset      | Source Markdown and optional structured specs                     |
| Vocabulary  | Canonical concept and field names, with aliases                   |
| Schemafier  | Build tool that extracts and reconciles documentation             |
| Schema      | One concept's fields, caveats, evidence, and review state in YAML |
| Schemaset   | A versioned collection of schemas                                 |
| Index       | Derived graph metadata and document embeddings for discovery      |
| Query layer | Local CLI and Python interfaces over those artifacts              |

**Core concepts**

A docset becomes a reviewed schemaset, used directly or through a derived search index.

[View Core concepts diagram](https://caseyrfsmith.github.io/scull/assets/diagrams/mermaid-4430bab3eda70d6e42c4-light.svg)

```mermaid
flowchart LR
    A[Docset and vocabulary] --> B[Schemafier]
    B --> C[Review]
    C --> D[Schemaset]
    D --> E[Exact lookup]
    D --> F[Index]
    F --> G[Search]
```

A **field** is an addressable fact or attachment point. A **caveat** describes a constraint or
exception, with evidence and applicability. A concept groups a bounded subject, such as an API
operation or command.

## What to ship

Exact lookup needs the schemaset. Semantic search also needs a compatible index and query embedding
provider. Format `0.2` schemas may reference a `constraints/` directory that must travel with them.

Building from prose needs a generative model; reading the finished schemas does not. Keep source
docs available because extraction can omit context.

Next: [quick start](https://caseyrfsmith.github.io/scull/docs/procedure/getting-started.md) or [schema format](https://caseyrfsmith.github.io/scull/docs/reference/schema-format.md).