Ludus FastMCP

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

No annotations are provided, so the description carries full burden. It effectively discloses key behavioral traits: it's a read-only operation (implied by 'Get' and 'Returns'), returns a dictionary structure, and provides example usage. However, it doesn't mention potential limitations like rate limits or authentication requirements.

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 perfectly structured: purpose statement, return value explanation, and practical example. Every sentence earns its place. The example is particularly valuable for showing how this tool integrates with create_custom_os_template.

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 parameterless tool with no annotations and no output schema, the description provides complete context. It explains what the tool does, what it returns, and how to use the results. The example bridges the gap to the sibling tool create_custom_os_template, making this description self-contained and actionable.

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 tool has 0 parameters with 100% schema description coverage. The description appropriately doesn't waste space discussing nonexistent parameters. It focuses on what the tool returns rather than inputs, which is correct for 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 with specific verb ('Get') and resource ('common ISO download URLs for popular operating systems'). It distinguishes from siblings by focusing on ISO URLs specifically, unlike other tools that handle templates, containers, or ranges.

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 explicitly states when to use this tool: 'that can be used with create_custom_os_template' and provides a concrete example showing the workflow. It clearly indicates this is a reference tool for obtaining ISO URLs to feed into another tool.

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