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

Annotations already provide readOnlyHint=true, destructiveHint=false, and idempotentHint=true, so the description's burden is lower. The description adds useful behavioral context: the batch shape '{ results, errors }', parameter size limit (1-50), and the specific fields returned. No contradictions.

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, front-loaded with the main purpose, then usage guidance, then batch format. Every sentence earns its place with no wasted words.

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 the tool has only one parameter and no output schema, the description covers the essential aspects: what it returns, when to use it, parameter constraints, and result shape. It could mention error handling for invalid IDs, but the batch shape implies that. Adequate for this complexity.

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. The description adds that `loan_ids` is an array with size limit 1-50 and that it returns a batch shape. However, it does not explain the format of each item in the array beyond what the schema already provides (strings). This adds some value but not full compensation for the lack of schema documentation.

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 verb 'Returns' and the resource 'full loan contract detail by id', and explicitly distinguishes from sibling tool openfinance_list_loans by advising to use it after that tool for deep-diving. This meets the criteria of specific verb+resource and sibling differentiation.

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 after openfinance_list_loans to deep-dive on a specific contract', providing clear when-to-use guidance and naming the alternative tool. This is exemplary usage guidance.

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