AWS Agent Registry Is Now Generally Available with a New API Namespace; Legacy AgentCore Interface to Be Retired in September

AWS announced the general availability of Agent Registry on August 31, providing a private catalog in which agents, tools, and skills distributed across different teams can be organized and searched by humans or agents. The Registry supports four record types: MCP servers containing tools, resources, and prompts; A2A agents described by Agent Cards; skills composed of Markdown files and software packages; and custom descriptions conforming to a JSON format. Records can be published through the console, CLI, SDK, or CI/CD pipelines, and external MCP or A2A endpoints can be connected directly to synchronize metadata.

Its architecture separates the “governance plane” from the “discovery plane.” The former retains draft, pending-review, rejected, and deprecated records, along with owners, versions, compliance tags, and approval status. The latter exposes only approved items to consumers and supports hybrid semantic and keyword search. The search API is also exposed as a remote MCP endpoint, allowing agents to find tools at runtime without loading the entire catalog into the prompt context in advance. CloudTrail logs control-plane operations, while EventBridge can trigger an organization’s own scanning or approval workflows when a record is submitted for review.

The generally available release adds support for managing the Registry with CloudFormation, AWS CDK, and Terraform; using tags to allocate costs or permissions; and creating cross-account, organization-wide catalogs through Resource Access Manager. Administrators can also enable automatic discovery at the AWS Organizations level. Newly created agents or MCP endpoints in AgentCore Runtime and Gateway are first added as drafts and then routed through the existing review process. This reduces the risk of unregistered “shadow agents,” but discovery remains focused on AgentCore resources observable by AWS and should not be treated as a cross-cloud asset inventory system.

The immediate engineering risk is the namespace migration. The generally available API has moved from `bedrock-agentcore` to the standalone `agent-registry` namespace, and support for the legacy interface will end on September 17. IAM actions, service endpoints, ARNs, EventBridge sources, and some data structures may need to be updated. Each Registry must also select either IAM SigV4 or JWT for inbound authorization when it is created, and the choice cannot be changed later. JWT-based catalogs currently cannot be queried through console search, the CLI, or SDKs because those clients rely on IAM signing. Finally, approval applies to catalog records, not to each tool action. Teams must still enforce least privilege, credential isolation, content scanning, and runtime authorization at the actual MCP or agent endpoints.