针对指标主题，查询指定时刻指标的最新值（瞬时查询）。使用 PromQL 语法对指标主题中的数据进行查询。注意：若该时刻向前推5分钟内均无指标数据，则无相应查询结果。 PromQL 语法示例： - 简单查询：ETLProcessingTraffic - 速率计算：rate(http_requests_total[5m]) - 聚合查询：sum(cpu_usage) by (instance) - 参考文档：https://cloud.tencent.com/document/product/614/90334
Accepts freeform code/query input (Query)
Part of the Cls MCP server. Enforce policies on this tool with Intercept, the open-source MCP proxy.
AI agents call QueryMetric to retrieve information from Cls 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 QueryMetric 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:
QueryMetric:
rules:
- action: allowSee the full Cls policy for all 19 tools.
Agents calling read-class tools like QueryMetric 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.
针对指标主题，查询指定时刻指标的最新值（瞬时查询）。使用 PromQL 语法对指标主题中的数据进行查询。注意：若该时刻向前推5分钟内均无指标数据，则无相应查询结果。 PromQL 语法示例： - 简单查询：ETLProcessingTraffic - 速率计算：rate(http_requests_total[5m]) - 聚合查询：sum(cpu_usage) by (instance) - 参考文档：https://cloud.tencent.com/document/product/614/90334. It is categorised as a Read tool in the Cls MCP Server, which means it retrieves data without modifying state.
Add a rule in your Intercept YAML policy under the tools section for QueryMetric. You can allow, deny, rate-limit, or validate arguments. Then run Intercept as a proxy in front of the Cls MCP server.
QueryMetric 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 QueryMetric 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 QueryMetric. 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.
QueryMetric is provided by the Cls MCP server (cls-mcp-server). Intercept sits as a proxy in front of this server to enforce policies before tool calls reach the server.
Open source. One binary. Zero dependencies.
npx -y @policylayer/intercept