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 mentions the return behavior ('Range information... or None if not found') but lacks details on permissions, rate limits, error handling, or what 'Range information' includes. For a lookup tool with zero annotation coverage, this is insufficient behavioral context.

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 front-loaded with the core purpose, followed by Args, Returns, and Example sections. Every sentence earns its place, with no redundant information, making it efficient and easy to parse.

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 (1 parameter, no output schema, no annotations), the description is adequate but has gaps. It explains the parameter and return behavior but lacks details on output format, error cases, or integration context. It meets minimum viability but could be more complete for operational use.

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 schema description coverage is 0%, but the description compensates by explaining the single parameter ('vm_name: Name of the VM to search for') and providing an example. It adds meaning beyond the bare schema, though it doesn't specify format constraints (e.g., case sensitivity). With 0% coverage and 1 parameter, this is above baseline.

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 a specific verb ('Find') and resource ('which range contains a specific VM by name'). It distinguishes itself from sibling tools like 'get_range', 'list_ranges', or 'list_hosts' by focusing on VM-to-range mapping rather than general range listing or host enumeration.

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 implies usage context (searching for a VM's range) but does not explicitly state when to use this tool versus alternatives. It doesn't mention prerequisites, exclusions, or compare with other search or lookup tools in the sibling list, though the purpose naturally suggests its niche.

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