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

With no annotations, the description carries the full burden. It discloses what the explanation covers (formulas, weights, limitations) but doesn't explicitly state that the tool is read-only, produces no side effects, or how the explanation is generated. For a zero-parameter informational tool this is acceptable, but not fully transparent.

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?

Two sentences, each earning its place: the first states the core action and content, the second gives a clear trigger for use. No filler, front-loaded, and perfectly sized for the purpose.

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 zero-parameter tool with no output schema, the description adequately covers purpose and when to use. It doesn't specify the response format, but it's reasonable to infer a textual explanation. A slight ambiguity about what 'the data' refers to is acceptable given the sibling context.

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 tool has zero parameters and the schema is empty, so schema description coverage is effectively 100%. The baseline for 0-parameter tools is 4, and the description adds no parameter confusion while still signaling that no inputs are needed.

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 states a specific verb ('Explain') and resource ('scoring formulas, weights, and honest limitations of the data'), which is unambiguous. It is clearly distinct from the sibling tools, which all focus on market research actions rather than explaining methodology.

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 explicitly says 'Use when a user questions the numbers,' providing a clear trigger condition. It doesn't name alternatives or exclusions, but the sibling tools are not genuine alternatives since none explain scoring methodology, so the guidance is sufficient but not exhaustive.

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