When to Use Tooling API

Use Tooling API when you need fine-grained access to an org’s metadata. Tooling API’s SOQL capabilities for many metadata types allow you to retrieve smaller pieces of metadata. Smaller retrieves improve performance, which makes Tooling API a better fit for developing interactive applications.

Because Tooling API allows you to change just one element within a complex type, it can be easier to use than Metadata API. Other use cases include:

Source control integration
Continuous integration
Apex classes or trigger deployment

Some of the specific tasks you can accomplish using the Tooling API:

Retrieve metadata about an object’s field.

Use FieldDefinition.
Retrieve custom or standard object properties.

Use EntityDefinition.
Manage working copies of Apex classes and triggers and Visualforce pages and components.

Use ApexClassMember, ApexTriggerMember, ApexPageMember, ApexComponentMember, and MetadataContainer.
Manage working copies of static resource files.

Use StaticResource.
Check for updates and errors in working copies of Apex classes and triggers and Visualforce pages and components.

ContainerAsyncRequest
Commit changes to your organization.

Use ContainerAsyncRequest.
Set heap dump markers.

Use ApexExecutionOverlayAction
Overlay Apex code or SOQL statements on an Apex execution.

Use ApexExecutionOverlayAction.
Execute anonymous Apex.

For sample code, see SOAP Calls and REST Overview.
Generate log files for yourself or for other users.

Set checkpoints with TraceFlag
Access debug log and heap dump files.

Use ApexLog and ApexExecutionOverlayResult.
Manage custom fields on custom objects.

Use CustomField.
Access code coverage results.

Use ApexCodeCoverage, ApexOrgWideCoverage, and ApexCodeCoverageAggregate.
Execute tests, and manage test results.

Use ApexTestQueueItem and ApexTestResult.
Manage validation rules and workflow rules.

Use ValidationRule and WorkflowRule.

See Also