Ludus FastMCP

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

No annotations are provided, so the description carries the full burden. It describes the tool as a list operation with detailed output, which implies it's read-only and non-destructive. However, it lacks details on potential behavioral traits like pagination, rate limits, authentication requirements, or error handling. The example output adds some context but doesn't fully compensate for the lack of annotations.

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 moderately concise but includes an extensive example that may be verbose. The first two sentences clearly state the purpose, but the 'Returns:' section and example add redundancy by detailing output structure without an output schema. While helpful, the example could be trimmed to improve front-loading of essential information.

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 tool's complexity (listing all ranges with details), no annotations, and no output schema, the description is partially complete. It covers the purpose and output structure via the example, but lacks information on behavioral aspects like performance, limitations, or error cases. The example compensates somewhat, but gaps remain for a tool in a rich sibling environment.

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 0 parameters with 100% coverage, so the schema fully documents the absence of inputs. The description doesn't need to add parameter semantics, but it correctly implies no required inputs through the example usage. The baseline for 0 parameters is 4, as the description aligns with the schema's indication of a parameterless tool.

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: 'List all ranges with detailed information including identification.' It specifies the verb ('List'), resource ('ranges'), and scope ('all' with 'detailed information'). However, it doesn't explicitly differentiate from sibling tools like 'list_ranges' or 'get_range', which might offer different levels of detail or filtering options.

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 minimal guidance on when to use this tool. It mentions 'making it easy to identify which range belongs to which user or purpose,' which implies a use case for identification, but doesn't specify when to choose this over alternatives like 'list_ranges' or 'get_range_by_user'. No explicit when-not-to-use or prerequisite information is provided.

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