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

Annotations already declare readOnlyHint=true, idempotentHint=true, destructiveHint=false, so safety profile is clear. Description adds batch response shape `{ results, errors }`, which is valuable behavioral context beyond 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?

Single paragraph but well-organized: purpose, field list, usage hint, parameter instruction. No unnecessary 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?

With no output schema, description lists many return fields and batch shape, making return format clear. Provides usage sequence. Missing explicit note on ID validity and error handling, but adequate for the 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 0% so description compensates by stating 'Pass loan_ids as an array (1-50)'. Adds format and cardinality constraints beyond the schema. Could specify that IDs come from list_loans, but sufficient.

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?

Clearly states it returns full loan contract detail by ID, lists specific fields (interestRates, installments, etc.). Distinguished from sibling openfinance_list_loans by explicit usage hint.

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?

Explicitly says 'Use after openfinance_list_loans to deep-dive on a specific contract,' providing context. Also specifies array size limit (1-50). Does not mention when not to use or alternative tools, but context is strong.

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