get_pair_rate

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

With no annotations, the description carries the behavioral disclosure burden. It does add a useful trait: the response depends on plan, with the converted amount only included on Pro or higher. However, it does not describe the return shape, rate basis, or edge-case behavior, leaving significant gaps.

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?

Two sentences, front-loaded with the purpose and no filler. The plan-level detail is relevant and earns its place.

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 and no annotations, the description is incomplete: it does not define the returned rate/result structure, behavior when amount is omitted, or how to select this over sibling tools. It covers availability but not enough for a fully informed call.

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 100%, so the schema already documents all four parameters. The description adds only 'optional precision' and 'amount/result', which do not materially extend the parameter meaning. Baseline credit is appropriate here.

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 names a specific verb ('Get'), resource ('exchange rate'), and scope ('single currency pair'), making the core function unambiguous. It also distinguishes itself from multi-pair or latest-rate tools by emphasizing 'single', though it does not explicitly differentiate itself from convert_currency.

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 is given about when to prefer this tool over convert_currency, get_latest_rates, or get_historical_rates. The only additional context is plan availability, which is not a use-case selector. The agent must infer usage from the schema and sibling names.

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