---
title: LLM topic blocks
description: Use this reference to understand the LLM topic blocks capabilities, supported request types, constraints, and key considerations when deploying conversational catalog requests.
locale: en-US
canonical_url: https://www.servicenow.com/docs/r/australia/servicenow-platform/service-catalog/llm-topic-blocks-reference.html
release: australia
product: Service Catalog
classification: service-catalog
topic_type: reference
last_updated: "2026-06-26"
reading_time_minutes: 1
breadcrumb: [Conversational Catalog Requests reference, Conversational Catalog Requests, Service Catalog, Manage service capabilities, Extend ServiceNow AI Platform capabilities]
---

# LLM topic blocks

Use this reference to understand the LLM topic blocks capabilities, supported request types, constraints, and key considerations when deploying conversational catalog requests.

-   **[Catalog Conversational Coverage](https://raw.githubusercontent.com/ServiceNow/ServiceNowDocs/australia/markdown/australia/servicenow-platform/service-catalog/using-catalog-conversational-experience.md)**  
ServiceNow® Catalog Conversational Coverage provides a dashboard to view a high-level overview of the conversational and non-conversational status of catalog items configured for the LLM topic block.
-   **[Guidelines for slot filling in catalog request](https://raw.githubusercontent.com/ServiceNow/ServiceNowDocs/australia/markdown/australia/servicenow-platform/service-catalog/c_slot_filling_ccr.md)**  
Conversational Catalog Requests uses a large language model \(LLM\) to extract variable values from a requester's input and pre-fill catalog item questions, a capability known as slot filling.
-   **[Prefill in conversational catalog request](https://raw.githubusercontent.com/ServiceNow/ServiceNowDocs/australia/markdown/australia/servicenow-platform/service-catalog/prefill-in-conversational-catalog-request.md)**  
The generalized prefill capability for conversational catalog request automatically populates catalog item form fields using data sourced from the requesting user's profile and from the active chat conversation history. This reduces manual data entry for requesters, improves form completion accuracy, and accelerates time-to-submission for service requests raised through the conversational interface.
-   **[Fulfillers can request catalog items for others](https://raw.githubusercontent.com/ServiceNow/ServiceNowDocs/australia/markdown/australia/servicenow-platform/service-catalog/fulfillers-request-catalog-items-for-others.md)**  
The experience for fulfillers streamlines the process of making catalog requests on behalf of others. This tailored workflow leverages parent context, such as incidents or cases, to improve efficiency, accuracy, and traceability of requests.
-   **[Request catalog item through Now LLM](https://raw.githubusercontent.com/ServiceNow/ServiceNowDocs/australia/markdown/australia/servicenow-platform/service-catalog/request-topic-blocks-va-llm.md)**  
You can design a topic conversation in Virtual Agent powered Now LLM by including reusable topic blocks to perform request submission tasks.

**Parent Topic:**[Reference](https://raw.githubusercontent.com/ServiceNow/ServiceNowDocs/australia/markdown/australia/servicenow-platform/service-catalog/catalog-agent-reference.md)