{"record":{"id":"ef43f213ff17e7cd","repo":"googleapis/mcp-toolbox","slug":"description-is-required-for-tool-q-ef43f2","errorCode":null,"errorMessage":"description is required for tool %q","messagePattern":"description is required for tool %q","errorType":"validation","errorClass":null,"httpStatus":null,"severity":"error","filePath":"internal/tools/spanner/spannerexecutesql/spannerexecutesql.go","lineNumber":69,"sourceCode":"\ntype Config struct {\n\ttools.ConfigBase `yaml:\",inline\"`\n\tType             string                 `yaml:\"type\" validate:\"required\"`\n\tSource           string                 `yaml:\"source\" validate:\"required\"`\n\tReadOnly         bool                   `yaml:\"readOnly\"`\n\tAnnotations      *tools.ToolAnnotations `yaml:\"annotations,omitempty\"`\n}\n\n// validate interface\nvar _ tools.ToolConfig = Config{}\n\nfunc (cfg Config) ToolConfigType() string {\n\treturn resourceType\n}\n\nfunc (cfg Config) Initialize(context.Context) (tools.Tool, error) {\n\tif cfg.Description == \"\" {\n\t\treturn nil, fmt.Errorf(\"description is required for tool %q\", cfg.Name)\n\t}\n\n\tsqlParameter := parameters.NewStringParameter(\"sql\", \"The sql to execute.\")\n\tparams := parameters.Parameters{sqlParameter}\n\n\tdefaultAnnotations := tools.NewDestructiveAnnotations\n\tif cfg.ReadOnly {\n\t\tdefaultAnnotations = tools.NewReadOnlyAnnotations\n\t}\n\n\treturn Tool{\n\t\tBaseTool: tools.NewBaseTool(\n\t\t\tcfg,\n\t\t\ttools.GetAnnotationsOrDefault(cfg.Annotations, defaultAnnotations),\n\t\t\ttools.Manifest{Description: cfg.Description, Parameters: params.Manifest(), AuthRequired: cfg.AuthRequired},\n\t\t\tparams,\n\t\t),\n\t}, nil","sourceCodeStart":51,"sourceCodeEnd":87,"githubUrl":"https://github.com/googleapis/mcp-toolbox/blob/8cc6e09de2ad7b8bffc77751799585a1401a48eb/internal/tools/spanner/spannerexecutesql/spannerexecutesql.go#L51-L87","documentation":"Config.Initialize in the spanner-execute-sql tool rejects configs with an empty Description. The description is required because it is surfaced in the MCP tool manifest for LLM clients; Initialize returns this error before building the tool.","triggerScenarios":"Initializing a spanner-execute-sql Config whose Description field is empty — usually a tools.yaml entry for kind spanner-execute-sql that lacks the `description` key.","commonSituations":"Omitting `description:` in tools.yaml; programmatic Config construction without Description; a YAML indentation mistake causing the field not to decode.","solutions":["Add a `description:` field to the spanner-execute-sql tool entry.","Set ConfigBase.Description when constructing Config programmatically.","Lint/validate your tools.yaml keys to catch silent empty-string decodes."],"exampleFix":"// before\nexecute-sql:\n  kind: spanner-execute-sql\n  source: my-spanner\n// after\nexecute-sql:\n  kind: spanner-execute-sql\n  source: my-spanner\n  description: Executes a SQL statement (DML or DDL) on Spanner.","handlingStrategy":"validation","validationCode":"if cfg.Description == \"\" {\n\treturn errors.New(\"spanner-execute-sql: description is required\")\n}","typeGuard":null,"tryCatchPattern":"cfg, err := decodeToolConfig(raw)\nif err != nil {\n\tif strings.Contains(err.Error(), \"description is required\") {\n\t\t// patch the config with a description before Initialize\n\t}\n\treturn err\n}","preventionTips":["Include `description:` in every spanner-execute-sql tool entry.","Add a pre-flight YAML validator that rejects tools lacking description.","Copy descriptions from the official prebuilt configs as a starting point."],"tags":["go","spanner","config","missing-field"],"backgroundTag":"missing-required-argument","analyzedSha":"8cc6e09de2ad7b8bffc77751799585a1401a48eb","analyzedAt":"2026-09-05T01:10:36.887Z","contentChangedAt":"2026-09-05T01:10:36.887Z","schemaVersion":2},"datasetVersion":"2026-09-08T10:18:20.063Z"}