rpg-mcp

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 states the tool performs a 'roll' but doesn't explain what happens during the roll (e.g., dice mechanics, modifiers applied), whether it's read-only or mutative, or any side effects. The mention of 'raw ability check' and 'uses only the ability modifier' adds some context but is insufficient for a tool with 7 parameters.

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 with no wasted words. It's front-loaded with the core purpose and includes clarifying details ('no skill proficiency', 'uses only the ability modifier') that earn their place by adding specificity.

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 complexity (7 parameters, no annotations, no output schema, low schema coverage), the description is inadequate. It lacks details on behavior, parameter usage, return values, and how it integrates with the system (e.g., what 'characterId' references). For a tool that likely involves game mechanics and multiple inputs, 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 low at 29%, with only 2 out of 7 parameters described in the schema. The description adds no parameter-specific information beyond the general 'ability modifier' hint, failing to compensate for the coverage gap. Parameters like 'advantage', 'disadvantage', 'dc', 'bonusModifier', and 'sessionId' remain unexplained in both schema and description.

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 ('Roll a raw ability check') and specifies the scope ('no skill proficiency', 'uses only the ability modifier'), which distinguishes it from general dice rolling. However, it doesn't explicitly differentiate from sibling tools like 'roll_skill_check' or 'roll_saving_throw', though the 'raw' and 'no skill proficiency' hints at this distinction.

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 minimal guidance by implying when to use it ('no skill proficiency'), but lacks explicit alternatives, prerequisites, or context for when to choose this over similar tools like 'roll_skill_check'. No when-not-to-use scenarios or comparisons to siblings are mentioned.

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