rpg-mcp

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

No annotations are provided, so the description carries the full burden of behavioral disclosure. It mentions 'distributions and expected values,' hinting at output types, but doesn't describe the return format, error conditions, computational limits, or whether it's a read-only vs. state-changing operation. For a tool with 6 parameters and no annotation coverage, this is insufficient, warranting a score of 2.

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 a single, efficient sentence: 'Calculate probabilities for dice rolls, including distributions and expected values.' It's front-loaded with the core purpose and adds a brief elaboration without waste. Every word earns its place, making it highly concise and well-structured for its length.

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 (6 parameters, 0% schema coverage, no annotations, no output schema), the description is incomplete. It states the purpose but fails to cover parameter meanings, behavioral traits, output details, or usage context. For a calculation tool with multiple inputs and no structured documentation, this minimal description is inadequate, resulting in a score of 2.

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%, meaning none of the 6 parameters are documented in the schema. The description doesn't add any parameter-specific information beyond the general purpose. It doesn't explain what 'expression', 'target', 'comparison', 'modifiers', 'exportFormat', or 'sessionId' mean or how they interact. This complete lack of parameter semantics results in a score of 1.

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: 'Calculate probabilities for dice rolls, including distributions and expected values.' It specifies the verb ('calculate') and resource ('probabilities for dice rolls'), and distinguishes it from siblings like 'dice_roll' (which likely performs actual rolls rather than calculations). However, it doesn't explicitly differentiate from all statistical tools in the sibling list, keeping it at a 4 rather than a 5.

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. It doesn't mention prerequisites, when-not-to-use scenarios, or compare it to other probability or dice-related tools in the sibling list (e.g., 'dice_roll', 'calculate_aoe'). This lack of contextual usage information results in a score of 2.

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