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CloudFormation operations

Every CloudFormation operation Overcast declares — 25 of 53 implemented — with status, behaviour notes and a link to the AWS API reference for each.

25 of 53 listed operations are implemented. Back to CloudFormation.

Summary

Category	✅ Supported	❌ Unsupported
Stacks	7	5
Change sets	5
Resources and events	3
Templates	3	1
Exports	2
Intrinsic functions	2
Dynamic references	3	1
Resource types		1
StackSets		13
Type registry		7

Endpoints

Stacks

Operation	Status	Notes	AWS Docs
`CreateStack`	✅ Supported	Async provisioner; JSON templates; intrinsic functions	docs
`UpdateStack`	✅ Supported	Re-provisions with updated template	docs
`RollbackStack`	✅ Supported	Rolls a CREATE_FAILED, UPDATE_FAILED, or UPDATE_ROLLBACK_FAILED stack back to a terminal rollback state	docs
`ContinueUpdateRollback`	✅ Supported	Retries a failed update rollback from UPDATE_ROLLBACK_FAILED; ResourcesToSkip, including nested-stack paths	docs
`DeleteStack`	✅ Supported	Async resource cleanup in reverse dependency order; DELETE_FAILED when a resource refuses deletion	docs
`DescribeStacks`	✅ Supported	Status, parameters, outputs, tags	docs
`ListStacks`	✅ Supported	StackStatusFilter, validated against the full StackStatus enum; unfiltered lists include DELETE_COMPLETE; summaries carry StackStatusReason	docs
`CancelUpdateStack`	❌ Unsupported	stub; returns 501	docs
`SignalResource`	❌ Unsupported	stub; returns 501	docs
`GetStackPolicy`	❌ Unsupported	stub; returns 501	docs
`SetStackPolicy`	❌ Unsupported	stub; returns 501	docs
`DescribeAccountLimits`	❌ Unsupported	stub; returns 501	docs

Change sets

Operation	Status	Notes	AWS Docs
`CreateChangeSet`	✅ Supported	Creates a change set from a template	docs
`DescribeChangeSet`	✅ Supported	Returns change set details and status; accepts ARN-only lookup	docs
`ExecuteChangeSet`	✅ Supported	Provisions resources via async provisioner; accepts ARN-only lookup	docs
`DeleteChangeSet`	✅ Supported		docs
`ListChangeSets`	✅ Supported	Lists active change sets for a stack	docs

Resources and events

Operation	Status	Notes	AWS Docs
`DescribeStackResources`	✅ Supported	Lists resources for a stack, with status and reason	docs
`ListStackResources`	✅ Supported	Lists resources with status	docs
`DescribeStackEvents`	✅ Supported	Returns stack provisioning events	docs

Templates

Operation	Status	Notes	AWS Docs
`GetTemplate`	✅ Supported	Returns the stack’s template body	docs
`GetTemplateSummary`	✅ Supported	Returns parameters and resource types	docs
`ValidateTemplate`	✅ Supported	Validates template syntax	docs
`EstimateTemplateCost`	❌ Unsupported	stub; returns 501	docs

Exports

Operation	Status	Notes	AWS Docs
`ListExports`	✅ Supported	Returns exports from all active stacks in region	docs
`ListImports`	✅ Supported	Returns stacks that import a given export name	docs

Intrinsic functions

Operation	Status	Notes	AWS Docs
`Fn::ImportValue`	✅ Supported	Cross-stack reference resolution	docs
`Fn::GetStackOutput`	✅ Supported	Weak cross-stack reference: any output of a stack in any region, no export needed; RoleArn accepted but not assumed	docs

Dynamic references

Operation	Status	Notes	AWS Docs
`{{resolve:secretsmanager}}`	✅ Supported	Secret by name or ARN; JSON key, version stage and version ID selectors	docs
`{{resolve:ssm}}`	✅ Supported	Plaintext parameter; an explicit version resolves to the current value	docs
`{{resolve:ssm-secure}}`	✅ Supported	Read with decryption, in the properties AWS enumerates only; an explicit version resolves to the current value	docs
`{{resolve:s3}}`	❌ Unsupported	Not resolved; fails the resource that uses it	docs

Resource types

Operation	Status	Notes	AWS Docs
`AWS::CloudFormation::WaitConditionHandle`	❌ Unsupported	Stub	docs

StackSets

Operation	Status	Notes	AWS Docs
`CreateStackSet`	❌ Unsupported	stub; returns 501	docs
`CreateStackInstances`	❌ Unsupported	stub; returns 501	docs
`DeleteStackSet`	❌ Unsupported	stub; returns 501	docs
`DeleteStackInstances`	❌ Unsupported	stub; returns 501	docs
`DescribeStackSet`	❌ Unsupported	stub; returns 501	docs
`DescribeStackInstance`	❌ Unsupported	stub; returns 501	docs
`DescribeStackSetOperation`	❌ Unsupported	stub; returns 501	docs
`ListStackSets`	❌ Unsupported	stub; returns 501	docs
`ListStackInstances`	❌ Unsupported	stub; returns 501	docs
`ListStackSetOperations`	❌ Unsupported	stub; returns 501	docs
`ListStackSetOperationResults`	❌ Unsupported	stub; returns 501	docs
`UpdateStackSet`	❌ Unsupported	stub; returns 501	docs
`UpdateStackInstances`	❌ Unsupported	stub; returns 501	docs

Type registry

Operation	Status	Notes	AWS Docs
`RegisterType`	❌ Unsupported	stub; returns 501	docs
`DeregisterType`	❌ Unsupported	stub; returns 501	docs
`DescribeType`	❌ Unsupported	stub; returns 501	docs
`DescribeTypeRegistration`	❌ Unsupported	stub; returns 501	docs
`ListTypes`	❌ Unsupported	stub; returns 501	docs
`ListTypeRegistrations`	❌ Unsupported	stub; returns 501	docs
`SetTypeDefaultVersion`	❌ Unsupported	stub; returns 501	docs

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