Ludus FastMCP

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

With no annotations provided, the description carries full burden for behavioral disclosure. While it mentions the tool performs rollback operations and returns results with successes/failures, it lacks critical behavioral details: no mention of permissions required beyond the vague 'admin only' note, no information about whether this is destructive (rollback typically implies data loss), no rate limits, no error handling specifics, and no details about what 'parallel' execution entails.

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 clear sections (purpose, args, returns) and uses minimal sentences. Each section adds value, though the 'admin only' note could be more precisely integrated. The structure is front-loaded with the core purpose first, followed by parameter and return details.

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 batch mutation tool with 3 parameters, 0% schema coverage, no annotations, and no output schema, the description provides basic but incomplete coverage. It covers the purpose, parameters at a high level, and return format concept, but lacks details about destructive nature, permissions, error conditions, and specific output structure. The absence of annotations and output schema increases the burden on the description, which it only partially meets.

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?

With 0% schema description coverage, the description provides good parameter context beyond the bare schema. It explains vm_names as 'List of VM names to rollback', snapshot_name as 'Name of snapshot to rollback to', and user_id as 'Optional user ID (admin only)'. This adds meaningful semantics, though it doesn't specify format constraints or provide examples for any parameters.

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 ('rollback') and resource ('multiple VMs to a snapshot'), and distinguishes it from the sibling tool 'rollback_snapshot' by specifying parallel/batch operation. The description explicitly mentions 'multiple VMs' and 'in parallel' which differentiates it from single-VM operations.

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 through the mention of 'parallel' operation and the optional 'admin only' user_id parameter, but doesn't explicitly state when to use this tool versus alternatives like 'rollback_snapshot' or other batch operations. No explicit when-not-to-use guidance or alternative tool recommendations are provided.

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