What causes "description is required for tool %q" in googleapis/mcp-toolbox?

Add a meaningful non-empty `description:` to the querylogs tool entry.

description is required for tool %q

Error message

description is required for tool %q

What it means

Config.Initialize for cloudloggingadmin-querylogs enforces a non-empty 'description' because it is required to build the MCP tool manifest. A missing or empty description aborts tool initialization with this error.

Source

Thrown at internal/tools/cloudloggingadmin/cloudloggingadminquerylogs/cloudloggingadminquerylogs.go:72

}

type Config struct {
	tools.ConfigBase `yaml:",inline"`
	Type             string                 `yaml:"type" validate:"required"`
	Source           string                 `yaml:"source" validate:"required"`
	Annotations      *tools.ToolAnnotations `yaml:"annotations,omitempty"`
}

// validate interface
var _ tools.ToolConfig = Config{}

func (cfg Config) ToolConfigType() string {
	return resourceType
}

func (cfg Config) Initialize(context.Context) (tools.Tool, error) {
	if cfg.Description == "" {
		return nil, fmt.Errorf("description is required for tool %q", cfg.Name)
	}

	startTimeDescription := fmt.Sprintf("Start time in RFC3339 format (e.g., 2025-12-09T00:00:00Z). Defaults to %d days ago.", defaultStartTimeOffsetDays)
	limitDescription := fmt.Sprintf("Maximum number of log entries to return. Default: %d.", defaultLimit)
	params := parameters.Parameters{
		parameters.NewStringParameter(
			"filter",
			"Cloud Logging filter query. Common fields: resource.type, resource.labels.*, logName, severity, textPayload, jsonPayload.*, protoPayload.*, labels.*, httpRequest.*. Operators: =, !=, <, <=, >, >=, :, =~, AND, OR, NOT.", parameters.WithStringRequired(false)),
		parameters.NewBooleanParameter("newestFirst", "Set to true for newest logs first. Defaults to oldest first.", parameters.WithBooleanRequired(false)),
		parameters.NewStringParameter("startTime", startTimeDescription, parameters.WithStringRequired(false)),
		parameters.NewStringParameter("endTime", "End time in RFC3339 format (e.g., 2025-12-09T23:59:59Z). Defaults to now.", parameters.WithStringRequired(false)),
		parameters.NewBooleanParameter("verbose", "Include additional fields (insertId, trace, spanId, httpRequest, labels, operation, sourceLocation). Defaults to false.", parameters.WithBooleanRequired(false)),
		parameters.NewIntParameter("limit", limitDescription, parameters.WithIntRequired(false)),
	}

	return Tool{
		BaseTool: tools.NewBaseTool(
			cfg,

View on GitHub (pinned to 8cc6e09de2)

Solutions

Add a meaningful non-empty `description:` to the querylogs tool entry.
Check indentation so description actually lands inside the tool's mapping.
Fix the tool named in the error message (cfg.Name) rather than scanning the whole file.

Example fix

// before
  query-logs:
    kind: cloud-logging-admin-query-logs
    source: my-logging-source
// after
  query-logs:
    kind: cloud-logging-admin-query-logs
    source: my-logging-source
    description: Queries Cloud Logging entries with an optional filter, start time, and limit.

Defensive patterns

Strategy: validation

Validate before calling

// Go: check required config fields before Initialize
if cfg.Name == "" || cfg.Description == "" {
    return nil, fmt.Errorf("tool %q: name and description are required", cfg.Name)
}

Try / catch

tool, err := cfg.Initialize(ctx)
if err != nil && strings.Contains(err.Error(), "description is required") {
    return nil, fmt.Errorf("tools.yaml: add description for tool %q", cfg.Name)
}

Prevention

Treat description as a mandatory field in your tools.yaml template.
Add a CI schema check (e.g. JSON schema / yamllint with required keys).
If generating configs programmatically, assert description non-empty before writing YAML.

When it happens

Trigger: Loading a tools.yaml whose cloudloggingadmin-querylogs tool entry lacks `description` or sets it to "".

Common situations: Minimal/hand-written tool configs; YAML nesting errors putting description at the wrong level; generated configs from scripts that leave description blank.

Understand the failure class

Background: "missing required argument" and "the following required arguments were not provided": what required-argument errors mean and how to fix them — this error's family across 20 libraries.

Related errors

AI-assisted analysis of googleapis/mcp-toolbox@8cc6e09de2 (2026-09-05). Data as JSON: /api/errors/d8fb738029a26b26. Report an issue: GitHub.