get_cost_basis

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

No annotations are provided, so the description carries the full burden. It states 'Get' which implies a read-only operation, and mentions the FIFO method and authentication. However, it does not disclose error handling, idempotency, or what happens if no matching card is found.

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 two sentences with no filler. Each sentence adds value: first states purpose, second gives parameter guidance. Perfectly concise.

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 no output schema and 0% param coverage, the description is somewhat complete but lacks details on response format, exclusivity enforcement (if both cardId and setCode provided), and default behavior (isFoil defaults to false). An agent might need additional 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?

Schema coverage is 0%, so the description must compensate. It explains the mutually exclusive parameter groups (cardId vs. setCode+setNumber) and implicitly addresses isFoil via 'card+finish'. This adds meaning beyond raw property names, but could be more explicit about isFoil.

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: 'Get FIFO cost basis for a specific card+finish for the authenticated user.' This distinguishes it from sibling tools like get_inventory_quantities or get_realized_gains, which handle different financial metrics.

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 specifies input alternatives: 'Pass either cardId or (setCode, setNumber).' It also mentions authentication requirement. However, it does not explicitly differentiate when to use this tool vs. other financial tools like get_portfolio_breakdown, leaving some ambiguity.

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