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 states this is a query (read-only operation) and implies it returns concentration details, but doesn't specify error conditions (e.g., what happens if the character isn't concentrating), permissions needed, or response format. For a tool with no annotation coverage, this is insufficient.

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 that front-loads the core purpose. Every word contributes directly to explaining what the tool does, with zero wasted text. It's appropriately sized for a simple query tool.

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 moderate complexity (2 parameters, no output schema, no annotations), the description is minimally adequate. It covers the basic purpose but lacks details on usage context, behavioral traits, and parameter explanations. Without annotations or output schema, the description should do more to compensate, but it meets the bare minimum for a read-only query.

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 50% (only 'characterId' has a description). The description adds no parameter-specific information beyond what's implied by the tool's purpose. It doesn't explain the 'sessionId' parameter or provide additional context for 'characterId'. With moderate schema coverage, the description doesn't compensate for the gaps, resulting in a baseline score.

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: 'Query what spell a character is currently concentrating on, including duration and targets.' It specifies the verb ('query'), resource ('spell a character is concentrating on'), and scope ('duration and targets'). However, it doesn't explicitly differentiate from sibling tools like 'check_concentration_duration' or 'break_concentration', which prevents a perfect score.

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 (e.g., requires a character to be concentrating), exclusions, or compare it to related tools like 'check_concentration_duration'. The lack of usage context leaves the agent to infer when this tool is appropriate.

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