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

Annotations already declare readOnlyHint=true and openWorldHint=true, covering safety. The description adds the World Bank source and frames the output as 'precise', but does not disclose data freshness, rate limits, or any behavioral quirks. This is adequate but not rich; baseline 3 with 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?

The description is concise and well-structured: purpose, indicator list, source, use case, and inputs are each given in one short sentence. Every sentence carries useful information, with no fluff or repetition.

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 simple read-only data retrieval tool with an output schema and annotations, the description is sufficient. It covers purpose, indicators, source, and usage trigger. The async behavior is already documented in the schema. Minor gap: no mention of data vintage or update frequency, but not essential.

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 is 100% with descriptions for all parameters, so the baseline is 3. The description repeats the indicator list and mentions country code format ('ISO-2 or ISO-3'), which slightly reinforces but does not substantially expand on 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 starts with a specific verb and resource: 'Return a precise macroeconomic indicator for a country'. It explicitly lists the available indicator names, distinguishing it from sibling tools like fx_rate or market_sizing by focusing on country-level macro figures from the World Bank.

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?

Provides clear when-to-use context: 'an agent's analysis needs an authoritative country-level economic figure.' It does not mention when not to use it or explicitly name alternative tools, so it misses the top-tier threshold for exclusion/alternative guidance.

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