Autocomplete a search term to find geographic areas (cities, counties, neighborhoods, school districts, states, etc.) and properties by address. Use this to look up boundary IDs for the boundary_id parameter in PropertySearch, OR Use this to look up property IDs for the id parameter in property d...
Risk signalsAccepts freeform code/query input (query)
Part of the Unlisted Property Search server.
Free to start. No card required.
AI agents call autocomplete_tool to retrieve information from Unlisted Property Search 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 autocomplete_tool 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": {
"autocomplete_tool": {}
}
}See the full Unlisted Property Search policy for all 3 tools.
These attack patterns abuse exactly the kind of access autocomplete_tool 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.
Autocomplete a search term to find geographic areas (cities, counties, neighborhoods, school districts, states, etc.) and properties by address. Use this to look up boundary IDs for the boundary_id parameter in PropertySearch, OR Use this to look up property IDs for the id parameter in property details tool. If a search does not yield the expected results attempt to simplify and/or shorten the query, removing potentially problematic or unneeded words/symbols. When telling the user what you're doing, say "area" not "boundary", and "home" or "property profile" not "listing". Don't mention internal IDs or parameter names.. It is categorised as a Read tool in the Unlisted Property Search MCP Server, which means it retrieves data without modifying state.
Register the Unlisted Property Search MCP server in PolicyLayer and add a rule for autocomplete_tool: 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 Unlisted Property Search. Nothing to install.
autocomplete_tool 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 autocomplete_tool 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 autocomplete_tool. 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.
autocomplete_tool is provided by the Unlisted Property Search MCP server (https://api.unlistedinc.com/mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.
Deterministic rules across all 3 Unlisted Property Search tools. Per-identity grants. Full audit log. Live in minutes. Nothing to install.
Free to start. No card required.
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