VictoriaMetrics-mcp-server

Instructions

Implementation Reference

• src/index.js:300-326 (handler)

  The handler function `vmLabelValues` that executes the tool logic: fetches unique values for the given label from VictoriaMetrics API endpoint `/api/v1/label/{label}/values` and returns the data as JSON or error.

  async function vmLabelValues(label) {
    let urlStr = VM_URL
    if (urlStr === "") {
      urlStr = VM_SELECT_URL
    }
    const url = new URL(urlStr + "/api/v1/label/"+ label +"/values");
    const response = await fetch(url.toString());
    const data = await response.json();
  
    if (data.status === "success") {
      return {
        content: [{
          type: "text",
          text: JSON.stringify(data.data),
        }],
        isError: false
      };
    } else {
      return {
        content: [{
          type: "text",
          text: "range query fail:" + await response.text(),
        }],
        isError: true
      };
    }
  }

• src/index.js:111-124 (schema)

  The tool schema definition for `vm_label_values`, including input schema requiring a `label` string parameter.

  const VM_LABEL_VALUES_TOOL = {
    name: "vm_label_values",
    description: "Get all unique values for a specific label",
    inputSchema: {
      type: "object",
      properties: {
        label: {
          type: "string",
          description: "Label name to retrieve values for",
        }
      },
      required: ["label"],
    }
  };

• src/index.js:127-134 (registration)

  Registration of the tool in the `VM_TOOLS` array, which is returned by the ListToolsRequestSchema handler for tool discovery.

  const VM_TOOLS = [
    VM_DATA_WRITE_TOOL,
    VM_QUERY_RANGE_TOOL,
    VM_QUERY_TOOL,
    VM_LABELS_TOOL,
    VM_LABEL_VALUES_TOOL,
    VM_PROMETHEUS_WRITE_TOOL
  ];

• src/index.js:359-362 (registration)

  The switch case in the CallToolRequestSchema handler that dispatches to the `vmLabelValues` handler function.

  case "vm_label_values": {
    const {label} = request.params.arguments;
    return await vmLabelValues(label);
  }