Single tool 'execute_skill_action' has critical definition gaps. Description is present (89 chars) but vague, does not explain WHAT operations it performs, WHEN to use it, or what it returns. Input schema exists with one parameter 'query_payload' (type: string) but lacks any constraint, format, or validation guidance. No output schema documented. Parameter description is generic ('Input execution payload') and does not specify expected format, structure, or examples. No error handling guidance. Tool name uses verb but is overly generic ('execute_skill_action' could mean anything). No security considerations documented despite WRITE risk classification. Fails baseline: 100% of A+ tools have documented return types; 100% of A+ tool params have descriptions with actionable constraints.

• Document output schema with all returned fields (e.g., anomaly_detection_id, metric_series_name, data_points_evaluated, anomalies_detected_count, outlier_indices, max_zscore_observed, distribution_skewness, statistical_report_url). Specify types and descriptions for each field.
• Expand tool description to 150-250 chars explaining: (1) What it does, detects statistical anomalies using Z-score analysis; (2) When to use it, when you need to identify outliers in time-series data; (3) What it returns, anomaly report with indices and Z-scores; (4) That it modifies state (WRITE).
• Add format and constraint guidance to 'query_payload' parameter. Specify expected structure (JSON object? CSV? SQL query?), required fields, and example payload. Replace generic description with actionable constraint: 'JSON object with metric_series_name (string) and values (array of numbers).'
• Rename tool from 'execute_skill_action' to 'detect_anomalies' or 'analyze_zscore_distribution' to match domain and follow verb_noun convention. This clarifies intent for LLM tool selection.
• Add error handling guidance: document what errors can occur (invalid payload format, empty values, insufficient data points), categorize as retryable or user-fixable, and provide recovery hints (e.g., 'If payload format is invalid, ensure values is an array of numbers').