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

Annotations already establish the read-only, idempotent, non-destructive profile. The description adds useful behavioral detail by limiting the result to the most recent value, capping at 6 countries, and indicating accepted country formats. It does not contradict any annotation.

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 tight sentences with the core operation front-loaded and the key usage hint immediately after. There is no filler, redundancy, or unnecessary detail.

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?

Together with the schema and annotations, the description provides the essential requirements: country formatting, country limit, and available indicators. It is slightly light on output shape or return-value expectations, but the comparison intent is sufficiently clear.

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?

Both parameters are fully described in the schema, including the allowed indicator list and an example, so the baseline applies. The description mostly restates the comma-separated country format with an added 6-country cap; useful but not a major semantic addition beyond the schema.

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 ('Compare'), the resource (most recent World Bank indicator value), and an explicit constraint (up to 6 countries). It clearly distinguishes this tool from siblings like worldbank_indicator or worldbank_country_profile by its multi-country comparison focus.

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?

It communicates the intended scenario (multi-country comparison of latest values) and gives the input format for supplying countries. It does not explicitly name alternative tools or state when not to use it, so it falls short of full routing guidance.

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