Get the keys in the object at path. Args: key: The name of the key path: The path in the JSON document Returns: List of keys or error message
AI agents call json_objkeys to retrieve information from AWS without modifying anything — typically the context-gathering step in research, monitoring, and reporting workflows, before the agent takes action elsewhere.
This tool performs a read-only operation to inspect JSON object keys. It has no side effects—it neither modifies data, executes code, deletes resources, nor commits financial transactions. The operation is informational only, making it a straightforward Read category with low severity since exposing JSON key names carries minimal risk of harm even if misused by an AI agent.
From the tool's definition Tool description states 'Get the keys in the object at path' with a return value of 'List of keys or error message'. This is a query operation that retrieves structure information from a JSON document without modifying, deleting, or executing anything.
Documented attack patterns abuse exactly the kind of access json_objkeys gives an agent:
PolicyLayer is an MCP gateway — it sits between your AI agents and AWS, and nothing reaches the server without passing your rules. This is the rule we recommend for json_objkeys:
{
"version": "1",
"default": "deny",
"tools": {
"json_objkeys": {}
}
}json_objkeys is read-only, so it stays allowed — but everything else on the server is denied unless you say otherwise.
Free to start. No card required.
Get the keys in the object at path. Args: key: The name of the key path: The path in the JSON document Returns: List of keys or error message. It is categorised as a Read tool in the AWS MCP Server, which means it retrieves data without modifying state.
Register the AWS MCP server in PolicyLayer and add a rule for json_objkeys: allow, deny, rate-limit, or require approval. Point your MCP client at the PolicyLayer proxy URL and the rule is enforced on every call, before it reaches AWS. Nothing to install.
json_objkeys 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 json_objkeys rule in your PolicyLayer 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 PolicyLayer policy for json_objkeys. 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.
json_objkeys is provided by the AWS MCP server (@awslabs/mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.
Start from AWS, add the rest of your stack, and see everything your agents can call. Then put policy on all of it.
Free to start. No card required.
300 AWS tools catalogued and risk-classified — across an index of 43,000+ MCP servers.