{"record":{"id":"1dcd5a1f21501535","repo":"flipped-aurora/gin-vue-admin","slug":"userrequirement-1dcd5a","errorCode":null,"errorMessage":"参数错误：userRequirement 必须是字符串类型","messagePattern":"参数错误：userRequirement 必须是字符串类型","errorType":"validation","errorClass":null,"httpStatus":null,"severity":"error","filePath":"server/mcp/gva_review.go","lineNumber":70,"sourceCode":"\t\t),\n\t\tmcp.WithString(\"generatedFiles\",\n\t\t\tmcp.Description(\"gva_execute创建的文件列表，JSON字符串格式，包含所有生成的后端和前端文件路径\"),\n\t\t\tmcp.Required(),\n\t\t),\n\t)\n}\n\n// Handle 处理审查请求\nfunc (g *GVAReviewer) Handle(ctx context.Context, request mcp.CallToolRequest) (*mcp.CallToolResult, error) {\n\t// 获取用户需求\n\tuserRequirementData, ok := request.GetArguments()[\"userRequirement\"]\n\tif !ok {\n\t\treturn nil, errors.New(\"参数错误：userRequirement 必须提供\")\n\t}\n\n\tuserRequirement, ok := userRequirementData.(string)\n\tif !ok {\n\t\treturn nil, errors.New(\"参数错误：userRequirement 必须是字符串类型\")\n\t}\n\n\t// 获取生成的文件列表\n\tgeneratedFilesData, ok := request.GetArguments()[\"generatedFiles\"]\n\tif !ok {\n\t\treturn nil, errors.New(\"参数错误：generatedFiles 必须提供\")\n\t}\n\n\tgeneratedFilesStr, ok := generatedFilesData.(string)\n\tif !ok {\n\t\treturn nil, errors.New(\"参数错误：generatedFiles 必须是JSON字符串\")\n\t}\n\n\t// 解析JSON字符串为字符串数组\n\tvar generatedFiles []string\n\terr := json.Unmarshal([]byte(generatedFilesStr), &generatedFiles)\n\tif err != nil {\n\t\treturn nil, fmt.Errorf(\"解析generatedFiles失败: %v\", err)","sourceCodeStart":52,"sourceCodeEnd":88,"githubUrl":"https://github.com/flipped-aurora/gin-vue-admin/blob/3136500ef380842b0eb6c4daa87c3f8a47fcf9e0/server/mcp/gva_review.go#L52-L88","documentation":"After confirming 'userRequirement' exists, Handle performs a Go type assertion userRequirementData.(string). The value must be a JSON string; if the argument was supplied as a number, object, array, bool or nil, the assertion fails and this error is returned. MCP arguments are loosely typed on the wire, so the server must defensively assert the expected type.","triggerScenarios":"Calling gva_review with 'userRequirement' present but not a JSON string, e.g. {\"userRequirement\": 123} or {\"userRequirement\": {\"text\": \"...\"}}.","commonSituations":"Client serialization turning the string into a number/bool; caller passing a nested object because they misunderstood the tool schema; JSON generators quoting/escaping incorrectly in the other direction (typed values).","solutions":["Send 'userRequirement' as a JSON string: {\"userRequirement\": \"your requirement text\"}.","Coerce the value to string on the client before invoking the tool (String(value) or equivalent).","Inspect the actual payload sent over the wire with a logger to confirm the runtime JSON type.","If the requirement contains structured data, serialize it to a string yourself before passing it."],"exampleFix":"// before\n{\"userRequirement\": 42}\n// after\n{\"userRequirement\": \"42 - 实现对应功能\"}","handlingStrategy":"type-guard","validationCode":"req := map[string]any{\"userRequirement\": fmt.Sprintf(\"%v\", requirementText)}\nif _, ok := req[\"userRequirement\"].(string); !ok {\n    return errors.New(\"userRequirement must serialize as a JSON string\")\n}","typeGuard":"func isString(v any) bool {\n    _, ok := v.(string)\n    return ok\n}","tryCatchPattern":null,"preventionTips":["Stringify values on the client before assigning them to MCP arguments.","Avoid letting serializers infer JSON types; declare the field as a string in the payload type.","Add a client-side assertion that the argument's JSON type is string for string-typed tool inputs."],"tags":["mcp","type-error","go","validation"],"backgroundTag":"type-assertion-failed","analyzedSha":"3136500ef380842b0eb6c4daa87c3f8a47fcf9e0","analyzedAt":"2026-08-31T13:50:02.721Z","schemaVersion":2},"datasetVersion":"2026-08-31T19:17:28.585Z"}