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

Annotations already indicate readOnlyHint, idempotentHint, and destructiveHint, so the description adds moderate behavioral context (e.g., batch response structure `{ results, errors }`). It doesn't mention error handling or rate limits, but overall consistent 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?

The description is a single paragraph with three sentences, front-loading purpose then fields, usage, and parameter details. No fluff, but could be more structured (e.g., bullet points for fields). Still efficient and informative.

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 complexity and lack of output schema, the description lists many fields and indicates the batch response shape. It also states the endpoint and usage context with sibling. Missing details like authentication are not critical and are covered by annotations.

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 0%, so the description compensates well by specifying 'Pass `loan_ids` as an array (1-50)', clarifying type and range. It also implies the parameter accepts up to 50 items, adding meaning beyond the raw schema.

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 returns full loan contract detail by ID, listing specific fields (interestRates, installments, etc.). It also distinguishes from the sibling tool openfinance_list_loans by advising to use it after listing, providing a clear verb+resource+context.

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?

Explicit guidance to use after openfinance_list_loans for deep-diving, and notes the batch parameter limit (1-50 IDs) and response shape. Though it doesn't explicitly state when not to use, the context is strong and covers key usage constraints.

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