get_cost_basis

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

Annotations already declare readOnlyHint=true, so the description doesn't need to confirm safety. It adds context about the data returned (FIFO cost basis) and the authentication requirement, which is valuable. No contradictions with annotations.

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 concise sentences front-load the core purpose and parameter options. No extraneous words; every sentence adds value.

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 is adequate for a simple tool but does not specify the return format (e.g., numeric value, currency) or error behavior (e.g., what if card not found). With no output schema, more detail on output would improve 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?

With 0% schema coverage, the description compensates by explaining the alternative identification methods (cardId or setCode+setNumber) and implicitly covering isFoil via 'finish'. However, it doesn't explicitly document the default for isFoil or the fact that setCode and setNumber must be used together.

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 retrieves FIFO cost basis for a specific card and finish. It specifies two identification methods (cardId or setCode+setNumber), distinguishing it from sibling tools like get_card or get_inventory_quantities.

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 parameter requirements but lacks guidance on when to use this tool versus alternatives (e.g., get_inventory_quantities, get_portfolio_breakdown). No explicit when-to-use or when-not-to-use context is given.

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