> ## Documentation Index > Fetch the complete documentation index at: https://docs.insight.nobly.dk/llms.txt > Use this file to discover all available pages before exploring further. # Keyword behaviour on a document type > Control how each assigned keyword behaves — required, read-only, hidden, unique, default values — and conditional keyword rules. ## Per-assignment behaviour When you assign a keyword to a document type, you also control **how it behaves** on that type's indexing form. The same keyword type can behave differently on different document types — required on one, hidden on another — because behaviour is set on the *assignment*, not on the keyword type itself. You set these on each keyword in the assignment editor under **Admin settings → Keywords → Keyword assignments**. To change one setting across many keywords at once, use [bulk edit](/configuration/keyword-assignment-models#bulk-editing). Keyword assignment editor showing each assigned keyword's required, hidden, read-only, unique, required-for-retrieval, and default value controls ## The behaviour flags | Behaviour | Effect | | -------------------------- | ------------------------------------------------------------------------------------------------------------------------------------------------ | | **Required** | The keyword must have a value before a document can be stored. Use it for the fields a document can't be filed without. | | **Required for retrieval** | The keyword must be supplied when *searching* for documents of this type — useful for narrowing large result sets. | | **Read-only** | The keyword is shown but can't be edited on the form. Use it for values set by the system or by automation. | | **Hidden** | The keyword isn't shown on the indexing form at all, while still existing on the document. Use it for values managed behind the scenes. | | **Unique** | The keyword's value must be unique across documents of this type — no two documents can share it. Use it for identifiers like an invoice number. | | **Default value** | A value pre-filled when a new document of this type is created. Users can change it unless the keyword is also read-only. | **Read-only** and **hidden** are different: a read-only keyword is *visible but locked*, a hidden keyword is *not shown at all*. Combine **default value** with **read-only** to stamp a fixed value users can see but not change. Be deliberate with **required** and **unique** on document types that already hold documents. Existing documents that don't satisfy a newly required or unique keyword can cause validation to fail the next time they're edited. ## Conditional keyword rules Beyond per-keyword flags, you can define **conditional rules** that change keyword behaviour based on other values — for example, show a keyword only when another keyword has a particular value, or set a default conditionally. Manage these under **Admin settings → Keywords → Keyword behavior**. Conditional rules are scoped per document type and are evaluated live on the indexing form as users enter values. They're the tool to reach for when a static *required* or *hidden* flag isn't enough and the behaviour needs to depend on context. The Keyword behavior settings page showing global keyword behaviour options and keyword conditional rules ## Where to read next Add the keywords whose behaviour you're configuring, as standalone fields or groups. The document types these keyword behaviours apply to.