Ludus FastMCP

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

With no annotations provided, the description carries the full burden of behavioral disclosure. It effectively describes key behavioral traits: it generates a 'FRESH configuration preview' (implying idempotent or non-destructive behavior), builds scenarios 'from scratch' with each call, and details what the preview includes (VMs, network topology, resource requirements, deployment estimates). It doesn't mention permissions, rate limits, or error handling, but covers the core operational behavior well.

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. It starts with a clear purpose statement, highlights important behavioral notes in uppercase, details parameters and returns in labeled sections, and ends with a practical workflow example. Every sentence adds value without redundancy, and the information is front-loaded for quick understanding.

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 complexity (previewing deployment scenarios), no annotations, and an output schema present, the description is complete. It explains the tool's purpose, when to use it, behavioral characteristics, parameter meanings, and what the preview returns (with specific examples like VM list and network topology). The output schema handles return value documentation, so the description focuses on operational context effectively.

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 input schema has 0% description coverage, so the description must compensate. It provides clear semantic explanations for all three parameters: 'scenario_key' as a 'Scenario identifier', 'siem_type' as 'SIEM type to include' with examples, and 'resource_profile' as 'Resource allocation profile' with options. This adds meaningful context beyond the bare schema, though it doesn't specify format constraints or validation rules.

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 explicitly states the tool's purpose: 'Preview a scenario before deployment with detailed information.' It specifies the verb ('preview'), resource ('scenario'), and distinguishes it from sibling tools like 'deploy_scenario' by emphasizing it's for verification before deployment. The description is specific and clearly differentiates from alternatives.

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 explicit guidance on when to use this tool: 'Use this BEFORE deploy_scenario to verify what will be deployed.' It includes a recommended workflow with step-by-step instructions, clearly positioning this as a pre-deployment verification step and naming the alternative tool ('deploy_scenario'). This gives clear context and exclusions.

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