Sakila MCP Server

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

No annotations are provided, so the description carries full burden. It mentions filtering capabilities but doesn't disclose important behavioral traits: whether results are paginated, what format they return, if there are rate limits, authentication requirements, or performance characteristics. For a search tool with 6 parameters and no annotations, this leaves significant gaps in understanding how it behaves.

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 appropriately concise - just two sentences that directly state the tool's purpose and filtering capabilities. It's front-loaded with the main function. There's no wasted text, though it could potentially benefit from slightly more structure or bullet points for the filter list.

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 search tool with 6 parameters, no annotations, and no output schema, the description is insufficient. It doesn't explain what the search returns (film objects? just titles?), how results are ordered, whether there's pagination, or any error conditions. The combination of missing behavioral context and lack of output information creates significant gaps for an agent trying to use this tool effectively.

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%, so the schema already documents all 6 parameters thoroughly. The description lists the same filter fields (title, category, rating, actor name) that appear in the schema, adding no additional semantic meaning beyond what's already in parameter descriptions. This meets the baseline for high schema coverage.

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 tool's purpose: 'search films' with filtering by title, category, rating, actor name, etc. It specifies the verb ('search') and resource ('films'), but doesn't explicitly differentiate from sibling tools like 'search_customers' or 'get_popular_films' which might have overlapping functionality. The purpose is clear but lacks sibling differentiation.

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 sibling tools like 'get_film_details' for single films or 'get_popular_films' for curated lists. There's no context about prerequisites, limitations, or when this search is preferred over other film-related tools.

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