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

Annotations already declare readOnlyHint=true, idempotentHint=true, destructiveHint=false and openWorldHint=false, covering the safety profile. The description adds genuinely new behavioral context by disclosing the quote convention of the returned data (INR per unit of USD, CNY and INR), which matters because there is no output schema.

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?

One sentence, no filler, and the core fact (what is returned and in what unit convention) is front-loaded. Every clause 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, the description must carry the return semantics, and it does specify the currencies and the per-unit quoting convention. It does not describe the response shape (e.g., map keyed by currency) or whether rates are static or periodically refreshed, which is a minor remaining gap for a zero-parameter getter.

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?

The tool takes zero parameters, so the baseline is 4 and there is nothing for the description to disambiguate. Schema coverage is 100% on an empty object, so no parameter detail is required.

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?

States a specific verb and resource ('Returns the exchange rates') and scopes it to IFC's landed-cost estimates, which ties it to the sibling estimate_landed_cost. It stops short of explicitly distinguishing itself from siblings, so it is clear but not fully differentiated.

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 link to 'landed-cost estimates' implies the context in which the tool is useful, but there is no explicit when-to-use statement, no prerequisite, and no mention of alternatives among the siblings. Usage is inferable rather than stated.

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