Sentinel MCP has solid naming conventions (all tools start with action verbs: get_, add_, update_, mark_, search_) and comprehensive descriptions (100-250 chars, well above the 34-char minimum). All 10 tools have input schemas with type definitions and parameter descriptions. However, output schemas are not documented, responses are returned as plain strings rather than structured JSON objects. Error handling is minimal; no recovery guidance or error classification. Tool descriptions include example user queries (good for discovery) but lack explicit state-change warnings for write operations. Parameters are well-described but lack enum constraints where applicable (e.g., 'status' should be constrained to 'active'|'paused'). No tool annotations (readOnlyHint, destructiveHint) despite clear read/write distinction in the Risk field.

• Document output schemas for all tools. Define structured response objects (e.g., MonitorItem with fields: id, product_name, shop, base_price, current_price, change_pct, status) so LLMs know what to extract.
• Add tool annotations: mark read-only tools with readOnlyHint=true; mark write tools (add_monitor, update_monitor_status, mark_alert_read) with destructiveHint=true or idempotentHint=true as appropriate.
• Add enum constraints to parameters: status in update_monitor_status and get_monitor_list should be enum ['active', 'paused']; add minItems/maxItems to limit parameter in get_alerts.
• Implement error recovery guidance: wrap tool implementations with try-catch that returns structured errors like {error: 'monitor_not_found', message: 'Monitor ID 123 not found. Try search_my_products() to find the correct ID.', retryable: false}.
• Add pagination to list/search tools: introduce offset/limit or cursor parameters; document max result limits (e.g., 'Returns up to 50 items; use offset to fetch more') in descriptions.

Inferred effective spec: <=2025-11-25.

• Relies on Logging (deprecated) - log to stderr or use OpenTelemetry