jeecgboot/JeecgBoot · warning · RuntimeException

未知工具: {toolName}

Error message

未知工具: {toolName}

What it means

handleToolsCall() dispatches tools/call by toolName across only 'hello', 'get_time', 'calculate'. Any other toolName throws a RuntimeException that becomes a tool-call error in the MCP response.

Source

Thrown at jeecg-boot/jeecg-boot-module/jeecg-module-demo/src/main/java/org/jeecg/modules/demo/mcp/McpDemoController.java:293

            }
            case "get_time" -> {
                yield "当前时间: " + LocalDateTime.now().format(DateTimeFormatter.ofPattern("yyyy-MM-dd HH:mm:ss"));
            }
            case "calculate" -> {
                double a = arguments.getDoubleValue("a");
                double b = arguments.getDoubleValue("b");
                String op = arguments.getString("operator");
                if (op == null) op = "+";
                double res = switch (op) {
                    case "+" -> a + b;
                    case "-" -> a - b;
                    case "*" -> a * b;
                    case "/" -> b != 0 ? a / b : Double.NaN;
                    default -> throw new RuntimeException("不支持的运算符: " + op);
                };
                yield String.format("%.2f %s %.2f = %.2f", a, op, b, res);
            }
            default -> throw new RuntimeException("未知工具: " + toolName);
        };
        
        return Map.of(
                "content", List.of(Map.of(
                        "type", "text",
                        "text", result
                ))
        );
    }

    /**
     * 使用说明页面
     */
    @IgnoreAuth
    @GetMapping("/info")
    @Operation(summary = "MCP Server 使用说明")
    public Map<String, Object> info(HttpServletRequest request) {
        log.info("[MCP Server] Hello 接口被访问");

View on GitHub (pinned to 96fb33f5ec)

Solutions

1. Call only hello, get_time, or calculate.
2. Re-fetch tools via tools/list to sync the client.
3. If you add a tool, register it in both the TOOLS array and the switch.

private static final Set<String> TOOL_NAMES = Set.of("hello","get_time","calculate");
String toolName = params.getString("name");
if (!TOOL_NAMES.contains(toolName)) {
    // return tool error: unknown tool, hint tools/list
}

// Return the error as a tool result (isError=true) so the MCP client surfaces it.
return Map.of("content", List.of(Map.of("type","text","text","未知工具: "+toolName)), "isError", true);

When it happens

Trigger: A client invokes a tool not present in the static TOOLS list; a typo in the tool name; client/server tool list out of sync.

Common situations: Generic MCP client cached an old tool list; typo; tool was renamed.

Related errors

• 未知方法: {method}
• 不支持的运算符: {op}
• 模板缺少参数：${item}
• The file name can not null
• 非法存储路径，路径包含遍历字符: {storePath}

AI-assisted analysis of jeecgboot/JeecgBoot@96fb33f5ec (2026-08-14). Data as JSON: /api/errors/12136488473facd2. Report an issue: GitHub.