App Hub overview
As you develop your cloud infrastructure, you might organize your Google Cloudresources across multiple projects. You might also have many resources withinone or multiple projects that provide an integrated business function that youwant to group logically. The resource hierarchy in Google Cloud can make itchallenging to manage and organize your infrastructure for these groupingpurposes. App Hub provides an application-centric way to group andmanage services and workloads, helping you align your infrastructure with yourbusiness functions.
App Hub acts as the foundational data model and central registry foryour applications on Google Cloud. It creates a single source of truth thatclarifies resource ownership, dependencies, and business context. This, in turn,supports other Google Cloud products with the application-centric context theyneed. For more information about this application-centric model and itsfeatures, seeApplication-centric Google Cloud.
This document provides a conceptual overview of App Hub to help youunderstand its capabilities and benefits before you set up or administer it.
Why use App Hub?
By shifting the focus from individual infrastructure resources to theapplications they form, App Hub helps you streamline governance andoperations at scale.
App Hub helps you implement the following application-centriccapabilities:
Streamline resource registration: Register at once multiple services andworkloads to an application. The limit for services and workloads that youcan register at a time is 10.
Organize and catalog your applications: Group scattered Google Cloudresources from one or more projects into logical App Hub applications.You can then find properties and categorize these applications withattributes like owners, business criticality, and environment to improvediscoverability and accountability. For more information, seeProperties and attributes.
Create a unified view for your teams: By defining an application inApp Hub, you provide essential context to other Google Cloudproducts. For example, you might enable the following features:
- A central view of operations and insights inCloud Hub, which displaysalerts, incidents, and performance data in an application context.
- AI-powered assistance fromGemini Cloud Assist,which uses App Hub's data model to help you design, operate,and troubleshoot your applications.
- Application monitoring withGoogle Cloud Observabilityto help you troubleshoot errors and improve performance by displayingtelemetry data for your applications and their components.
Clarify ownership and dependencies: Understand how your applications arecomposed and how their components depend on each other. This feature helpsdevelopers and operators visualize application architecture, identifyowners, and resolve issues.
To learn more about how App Hub fits into the broader applicationlifecycle, seeApplication-centric Google Cloud.
App Hub concepts and data model
App Hub is built on a data model based on the following key concepts:applications, services, and workloads. These terms are common in the industry,but App Hub uses them in a specific way.
The following table compares the App Hub definition with commonindustry usage:
| Concept | App Hub definition | Common industry usage |
|---|---|---|
| Application | A logical grouping of services and workloads that together deliver a business function. | Can refer to a single deployable unit, a codebase, or a broad system. |
| Service | A network or API interface that exposes functionality to clients and can route requests to workloads, such as a load balancer. Some services, such as GKE clusters, are designated asshared services that you can register to multiple applications. This is indicated by their registration typeproperty. | Often refers to a microservice, a deployable component, or binary code with its own business logic and data. |
| Workload | The compute resources where the binary deployments of your application are installed. The application code from these resources performs a discrete part of your business logic. For example, a workload can be a GKE deployment or a Compute Engine managed instance group (MIG) running the code of an AI agent. | A more general term for any process or component that consumes computing resources. |
For more information about these and other Application-centric Google Cloud central concepts, seeKey concepts. For a list of supported resources inApp Hub that you can register as services or workloads in yourapplications, seeApp Hub supported resources.
You can define App Hub applications based on your geographicdistribution requirements. Your location choice impacts which services andworkloads you can register in applications and can be important for dataresidency requirements. You can designate the following locations:
- Global applications: group services and workloads from multipleGoogle Cloud regions.
- Regional applications: group services and workloads that all residewithin a single region.
For a detailed comparison to help you choose the right location, seeGlobal and regional applications.
Services and workloads show aregistration status inyour applications. Additionally, applications, services, and workloads cancontain metadata in the form ofproperties and attributes.
You can view details of your deployed applications and their services andworkloads, including location, registration status, and metadata. For moreinformation, seeView details of services and workloadsandView application details.
Registration status of services and workloads
The organizational structure of your Google Cloud resources affects howApp Hub can manage services and workloads and lets you registerthem in applications. Services and workloads that you canregister to an application have one of thefollowing registration status:
Discovered: Services and workloads that you can register to anapplication because they are part of theapplication management boundary andthat aren't registered to any other application or can be registered tomultiple applications. The discovered status also includes services andworkloads that you delete or unregister from an application but that you canregister again.
Note: Even if you have registered shared services to an application, theycan have a registration status ofdiscovered in other applications.Registered: Services and workloads registered to an application andmanaged by App Hub. You can only register discovered services andworkloads. After you register the service or workload, the registrationstatus updates fromdiscovered toregistered.
Detached: Services or workloads that have been registered to anapplication, but that App Hub can't manage or monitor because theirunderlying Google Cloud resources are no longer part of theapplication management boundary that you have defined. The registration status ofservices and workloads registered to an application can change todetachedfor the following reasons:
- The underlying resource is deleted. For example, if you delete aforwarding rule represented by a service, the service's registrationstatus changes todetached.
- A project or folder containing underlying resources for registeredservices or workloads is moved out of the application management boundary.
Detached services and workloads remain in the application until youunregister them.
If you move a project out of the application management boundary, its detachedservices and workloads can become discoverable for applications in adifferent boundary. You canregisterdiscoverable services and workloads again, adhering to theresource hierarchyestablished by the application management boundary.
To select an application management boundary that fits your resource hierarchy inGoogle Cloud and let App Hub discover and register the services andworkloads that your business needs, seeChoose your application setup model. To view theregistration status of services and workloads, seeView details of services and workloads.
Properties and attributes
To enrich the data model, App Hub lets you expose properties andattributes to support application discoverability, accountability, andgovernance. Defining these values as application metadata helps you filter,manage, and apply policies to your application components at scale.
To view the properties and attributes of the services and workloads in yourapplications, seeView details of services and workloads.
The following are the definitions and features of properties and attributes:
Properties are immutable fields that describe the underlyinginfrastructure of a registered service or workload, such as the project ID,location, or type. These are discovered automatically and cannot be editedin App Hub. Key supported properties include:
(Preview)Registration type: for services, an output-only property thatindicates if a service can be registered to one or multipleapplications. The following are the possible values for this property:
EXCLUSIVE: you can only register the service to a singleapplication.SHARED: you can register the service to multiple applications.This value indicates that the service is ashared service.
To learn which services are shared or exclusive, seethe list of App Hub supported services.
(Preview)Functional type: an output-only property that identifies the knownfunction of a service or workload. For example, when an AI agent isdeployed through a managed platform likeVertex AI Agent Engine,App Hub automatically classifies the resource with the
AGENTfunctional type value to indicate that the workload runs an AI agent.(Preview)Extended metadata: an schema-driven property that provides rich,structured information about the service or workload. It refers to akey-value field that adds detailed, type-specific data. For example,workloads with a functional type value of
AGENTcan includeapphub.googleapis.com/AgentPropertiesmetadata, which containsinformation about an agent that is compatible with theAgent2Agent (A2A) Agent Card.For a list of supported metadata types and their schemas, seeExtended metadata schemas.To learn how to visualize this metadata, seeView extended metadata schemas.(Preview)Identity: an output-only property that contains the service accountor managed workload identity name for a service or workload.
Attributes are mutable, user-defined metadata that you can apply toapplications, services, and workloads to organize and govern them.You can add attributes to applications, services, and workloads when youcreate an application and register resources to it.You can alsoupdate service and workload attributesandupdate application attributes.Key attributes include:
Owners: Contact information for developer, operator, and businessteams. The supported owner types are:
developer_owners: Development team that owns development andcoding.operator_owners: Operator team that ensures runtime and operationsintegrity.business_owners: Business team that ensures quality and userexpectations are met.
Criticality: The importance of the component to your business. Thesupported values are:
MISSION_CRITICALHIGHMEDIUMLOW
Environment: The lifecycle stage of the component. The supportedvalues are:
PRODUCTIONSTAGINGDEVELOPMENTTEST
The App Hub resource model
To enable application-centric features, App Hub uses a resource modelcentered on the concepts of themanagement project and theapplication management boundary.
- Recommended:Folder-level boundary:If your components are organized within a Google Cloud folder structure, youcan use a folder as your boundary. This approach aligns yourapplication management boundary with your organization's structure by business unit,environment, or team, and automatically includes all projects within thatfolder.
- (Preview)Single-project boundary:For small applications where all Google Cloud resources reside in oneproject, you can designate that single project as your boundary.This is the quickest way to get started with application management.You can define single-project boundaries by configuring theproject as a standalone management project.
- (Legacy) Multiple-project boundary with a host project: Forexisting users, App Hub supports a legacy model where you candesignate a host project for application management by enabling theApp Hub API on a Google Cloud project. Then, you manually connectother Google Cloud projects, known as service projects, to it formulti-project resource discovery.
This application management layer that App Hub introduces on top ofyourresource hierarchy in Google Cloudlets App Hub discoversupported resourceswithin the boundary. You can choose a setup model for applications andset an application management boundary that best fits your resource hierarchy andgovernance needs.
For information about data handling in this resource organization and otherapplication-centric features, seeApplication-centric Google Cloud.For details about getting started and defining an application management boundary, seeChoose your application setup model.
What's next
- To see which Google Cloud resources you can register in App Hub,seeSupported resources.
- To get started with defining an application management boundary, seeChoose your application setup model.
- To understand the permissions required to use App Hub, seeRoles and permissions.
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Last updated 2026-02-19 UTC.