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 mentions 'admin only' for user_id, which hints at permission requirements, but doesn't disclose whether this is a destructive operation, what 'applying' does to the VM (e.g., reboots, configuration overwrites), error handling, or rate limits. The return value is mentioned but not explained.

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 with a clear opening sentence followed by Args and Returns sections. It's front-loaded with the core purpose. However, the 'Returns' line is vague ('Template application result') and could be more informative without adding bulk.

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 no annotations, 0% schema coverage, but an output schema exists, the description is moderately complete. It covers the basic purpose and parameters, but lacks behavioral details (e.g., side effects, prerequisites) and doesn't leverage the output schema to explain return values. For a mutation tool with admin constraints, more context is needed.

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 description must compensate. It lists all three parameters with brief explanations: vm_name identifies the target, template_id specifies what to apply, and user_id is optional/admin-only. This adds meaning beyond the bare schema, but doesn't detail formats (e.g., template_id syntax) or constraints (e.g., VM state requirements).

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 action ('Apply') and target ('a template to a VM'), making the purpose understandable. It distinguishes from siblings like 'add_template' or 'build_template' by focusing on application rather than creation. However, it doesn't specify what 'applying' entails (e.g., configuration changes, deployment).

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. With many sibling tools like 'deploy_range', 'apply_adversary_profile', and 'apply_defender_profile', there's no indication of how this differs or when it's appropriate. The only contextual hint is the 'admin only' note for user_id, but this doesn't address tool selection.

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