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

The description adds behavior not fully covered by annotations: it is a paid call ($0.15/call), it uses the Public Store API for candidates only, and it does not fetch the portfolio. This clarifies the operational context and constraints. However, side effects are not fully described, and annotations already indicate non-read-only status.

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 sentence that concisely conveys functionality, constraints, and pricing. It is front-loaded with the main action and resource, and every clause carries meaningful information without unnecessary elaboration.

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?

The description explains what the tool does and key constraints, but since there is no output schema, it does not describe the return format or how rankings are presented. Given the tool's complexity (7 parameters, including arrays and enums), more detail about output and expected behavior would be needed for full completeness.

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 100% documentation coverage for all 7 parameters, including types, defaults, constraints, and descriptions. The tool description does not add any parameter-level meaning beyond the schema, so the baseline of 3 is appropriate.

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: it ranks candidate niches by public Store opportunity and adjacency to a user-supplied portfolio. The verb 'rank' is specific and the resource ('candidate niches') is well-defined. It distinguishes itself from sibling tools by focusing on portfolio expansion and explicitly noting it does not fetch portfolio data.

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 context about scope (uses Public Store API, does not fetch portfolio) but does not explicitly state when to use this tool over its siblings. No alternatives or exclusions are mentioned, leaving the decision to the agent based on the name and purpose alone.

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