This record as markdown: /tools/io-github-portel-dev-ncp/query-collection.md
What query_collection does on Ncp
AI agents call query_collection to retrieve information from Ncp without modifying anything. It is typically the context-gathering step in research, monitoring, and reporting workflows, before the agent takes action elsewhere.
Why query_collection is rated Low
This tool performs a read operation against a Firestore database. While it retrieves data (Read category), the severity is medium rather than low because: (1) Firestore queries can return sensitive data depending on collection contents and access patterns, (2) an AI agent could potentially construct queries to extract unintended information, and (3) the tool operates in an N-to-1 orchestration context where…
From the tool's definition Tool name 'query_collection' and description 'Query Firestore collection' indicate data retrieval from a database without modification capabilities.
Attacks that exploit this kind of access
The rule that runs query_collection safely
PolicyLayer is an MCP gateway: it sits between your AI agents and Ncp, and checks every tool call against a rule you set before the call runs. Nothing changes on the server itself. For query_collection, this is the rule to start with:
query_collection is read-only, so it stays allowed. Everything else on the server is denied unless you say otherwise.
The button opens the PolicyLayer dashboard: create your workspace, connect Ncp, apply this rule, and every query_collection call is checked against it from then on.
Questions about query_collection
Query Firestore collection. It is categorised as a Read tool in the Ncp MCP Server, which means it retrieves data without modifying state.
Register the Ncp MCP server in PolicyLayer and add a rule for query_collection: 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 Ncp. Nothing to install.
query_collection 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 query_collection 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 query_collection. 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.
query_collection is provided by the Ncp MCP server (@portel/ncp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.
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