Sakila MCP Server

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

With no annotations provided, the description carries the full burden of behavioral disclosure. It states this is a retrieval operation ('取得します'), implying it's likely read-only, but doesn't explicitly confirm this or mention any authentication requirements, rate limits, error conditions, or what happens if the film isn't found. The description adds minimal behavioral context beyond the basic purpose.

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 that communicates the core purpose and scope without unnecessary words. It's appropriately sized for a simple retrieval tool and front-loads the essential information. Every element of the sentence contributes meaning.

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?

For a retrieval tool with no annotations and no output schema, the description is insufficiently complete. It doesn't describe what the return format looks like (structure of the detailed information), whether it returns a single result or multiple, error handling, or any behavioral constraints. Given the complexity of returning detailed film information with multiple data points, more context would be helpful for the agent.

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?

Schema description coverage is 100% (the single parameter 'title' has a clear description in Japanese), so the baseline is 3. The tool description doesn't add any parameter-specific information beyond what's in the schema - it doesn't explain format expectations, examples, or constraints for the title parameter. The description's mention of what details are retrieved doesn't directly relate to parameter semantics.

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 verb ('取得します' - get/retrieve) and resource ('映画の詳細情報' - film details), specifying what information is included ('出演者、カテゴリ、在庫状況含む' - including cast, category, inventory status). It distinguishes from siblings like 'check_film_availability' (which might only check availability) and 'search_films' (which likely returns a list rather than detailed information). However, it doesn't explicitly differentiate from 'get_actor_filmography' or 'get_category_performance' which focus on different aspects.

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 when to choose this over 'search_films' (which might return multiple films with less detail) or 'check_film_availability' (which might focus only on inventory). There's no context about prerequisites, timing, or exclusions for usage.

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