Sakila MCP Server

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

No annotations are provided, so the description carries the full burden of behavioral disclosure. It only states what the tool does (get overdue rentals) without mentioning any behavioral traits like whether it's read-only, if it requires specific permissions, rate limits, or what the output format might be. For a tool with zero annotation coverage, this is a significant gap.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is a single, efficient sentence in Japanese that directly states the tool's purpose without any unnecessary words. It is appropriately sized and front-loaded, making it easy to understand at a glance.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

Given the complexity of a tool with 3 parameters and no output schema or annotations, the description is incomplete. It doesn't cover behavioral aspects, usage context, or output details, leaving gaps that could hinder an AI agent's ability to use the tool effectively. This is inadequate for a tool with multiple parameters and no structured support.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

The input schema has 100% description coverage, with all parameters well-documented in the schema itself (e.g., store_id, days_overdue, limit with defaults). The description adds no additional meaning beyond what the schema provides, such as explaining parameter interactions or usage examples. With high schema coverage, the baseline score of 3 is appropriate.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

The description clearly states the purpose: '延滞中のレンタル一覧を取得します' (Get a list of overdue rentals). It specifies the verb (get/取得) and resource (overdue rentals/延滞中のレンタル). However, it doesn't explicitly differentiate from sibling tools like 'get_customer_rentals' or 'get_customer_activity', which might also involve rental data, so it doesn't reach the highest score.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

The description provides no guidance on when to use this tool versus alternatives. It doesn't mention any context, prerequisites, or exclusions, such as how it differs from other rental-related tools like 'get_customer_rentals' or 'search_films'. This leaves the agent without clear usage instructions.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.