Lists the registries in your account. REQUIREMENTS: - For AWS service events, you MUST use the aws.events registry directly - For custom schemas, you MAY use LOCAL scope to manage your own registries - When searching AWS service events, you SHOULD use the AWS scope USAGE PATTERNS: 1. Finding AW...
Part of the AWS Serverless MCP Server MCP server. Enforce policies on this tool with Intercept, the open-source MCP proxy.
AI agents call list_registries to retrieve information from AWS Serverless MCP Server without modifying any data. This is common in research, monitoring, and reporting workflows where the agent needs context before taking action. Because read operations don't change state, they are generally safe to allow without restrictions -- but you may still want rate limits to control API costs.
Even though list_registries only reads data, uncontrolled read access can leak sensitive information or rack up API costs. An agent caught in a retry loop could make thousands of calls per minute. A rate limit gives you a safety net without blocking legitimate use.
Read-only tools are safe to allow by default. No rate limit needed unless you want to control costs.
tools:
list_registries:
rules:
- action: allowSee the full AWS Serverless MCP Server policy for all 32 tools.
Agents calling read-class tools like list_registries have been implicated in these attack patterns. Read the full case and prevention policy for each:
Other tools in the Read risk category across the catalogue. The same policy patterns (rate-limit, allow) apply to each.
Lists the registries in your account. REQUIREMENTS: - For AWS service events, you MUST use the aws.events registry directly - For custom schemas, you MAY use LOCAL scope to manage your own registries - When searching AWS service events, you SHOULD use the AWS scope USAGE PATTERNS: 1. Finding AWS Service Event Schemas: - Use aws.events registry directly instead of searching - Filter by AWS scope to see only AWS-provided schemas 2. Managing Custom Schemas: - Use LOCAL scope to view your custom registries - Apply registry_name_prefix to find specific registry groups. It is categorised as a Read tool in the AWS Serverless MCP Server MCP Server, which means it retrieves data without modifying state.
Add a rule in your Intercept YAML policy under the tools section for list_registries. You can allow, deny, rate-limit, or validate arguments. Then run Intercept as a proxy in front of the AWS Serverless MCP Server MCP server.
list_registries is a Read tool with low risk. Read-only tools are generally safe to allow by default.
Yes. Add a rate_limit block to the list_registries rule in your Intercept policy. For example, setting max: 10 and window: 60 limits the tool to 10 calls per minute. Rate limits are tracked per agent session and reset automatically.
Set action: deny in the Intercept policy for list_registries. The AI agent will receive a policy violation error and cannot call the tool. You can also include a reason field to explain why the tool is blocked.
list_registries is provided by the AWS Serverless MCP Server MCP server (awslabs.aws-serverless-mcp-server). Intercept sits as a proxy in front of this server to enforce policies before tool calls reach the server.
Deterministic policy on every MCP tool call. Per-identity grants. Full audit log.