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 of behavioral disclosure. It mentions that user_id is 'admin only,' which adds some context about authorization needs. However, it lacks details on rate limits, error conditions, whether this is a read-only operation (implied by 'Get' but not explicit), or any side effects. For a tool with no annotation coverage, this leaves significant gaps in behavioral understanding.

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 well-structured and appropriately sized, with a clear purpose statement followed by Args and Returns sections. Each sentence earns its place by providing essential information without redundancy. However, it could be slightly more front-loaded by integrating the admin hint into the main purpose, preventing a perfect score.

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 low complexity (one optional parameter) and the presence of an output schema (which handles return values), the description is mostly complete. It covers the purpose, parameter semantics, and return content adequately. The main gap is the lack of behavioral details like permissions or side effects, but with an output schema reducing the need to explain returns, it's reasonably comprehensive for this context.

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 0%, so the schema provides no parameter descriptions. The description adds value by explaining that user_id is 'Optional user ID (admin only),' clarifying its optionality and admin restriction. However, it doesn't fully compensate for the coverage gap—for example, it doesn't explain what 'range' refers to or how the user_id affects the output. With one parameter and partial semantic addition, a baseline 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 tool's purpose: 'Get /etc/hosts entries for the range.' This specifies the verb ('Get') and resource ('/etc/hosts entries for the range'), making it immediately understandable. However, it doesn't explicitly differentiate from sibling tools like 'get_range_config' or 'get_range', which might also retrieve range-related information, 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 some implied usage context by mentioning 'admin only' for the user_id parameter, suggesting this tool may require administrative privileges. However, it doesn't explicitly state when to use this tool versus alternatives (e.g., compared to 'get_range_config' or other 'get_range_*' tools), nor does it outline any prerequisites or exclusions beyond the admin hint.

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