Check if data from another agent is recent and valid based on timestamps, staleness indicators, and expected update frequencies. Prevents acting on outdated information.
Part of the Agent Output Guard server.
Free to start. No card required.
AI agents call validate_data_freshness to retrieve information from Agent Output Guard 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 validate_data_freshness 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.
{
"version": "1",
"default": "deny",
"tools": {
"validate_data_freshness": {}
}
}See the full Agent Output Guard policy for all 5 tools.
These attack patterns abuse exactly the kind of access validate_data_freshness gives an agent. Each links to the full case and the policy that stops it:
Other read tools across the catalogue. The same approach applies to each: allow, with a rate cap to control cost.
Check if data from another agent is recent and valid based on timestamps, staleness indicators, and expected update frequencies. Prevents acting on outdated information.. It is categorised as a Read tool in the Agent Output Guard MCP Server, which means it retrieves data without modifying state.
Register the Agent Output Guard MCP server in PolicyLayer and add a rule for validate_data_freshness: 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 Agent Output Guard. Nothing to install.
validate_data_freshness 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 validate_data_freshness 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 validate_data_freshness. 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.
validate_data_freshness is provided by the Agent Output Guard MCP server (@agenson-horrowitz/agent-output-guard-mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.
Deterministic rules across all 5 Agent Output Guard tools. Per-identity grants. Full audit log. Live in minutes. Nothing to install.
Free to start. No card required.
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