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

Without annotations, the description should explain behavioral traits (e.g., rate update frequency, error handling for invalid currencies, API limits). It only mentions using ECB rates, omitting other behavioral nuances.

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?

A single concise sentence that conveys the core purpose efficiently. However, it could be slightly more structured but remains front-loaded and clear.

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?

For a tool with 3 required parameters, no output schema, and no annotations, the description provides insufficient guidance. Missing information on output format, error states, and usage 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 has 3 parameters with 0% description coverage. The description does not add meaning beyond parameter names, e.g., no mention of ISO 4217 format, amount constraints, or required precision.

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?

Description clearly states verb 'Convert', resource 'amount between currencies', and data source 'latest ECB rates', distinguishing it from sibling tools like currency_list and currency_rates.

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?

No guidance on when to use this tool versus alternatives (e.g., currency_list for listing currencies, currency_rates for rates only). The description does not specify prerequisites or exclusion conditions.

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