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

Annotations already declare this as a safe read-only operation, so the bar is lower. The description adds useful behavioral context: it notes the data is a 'static composite' with 'semi-annual update' and provides an example of the output values, which informs the agent about the nature and freshness of the data. No contradictions 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 front-loaded with the primary usage guidance. Four sentences cover usage, return content, an illustrative example, and source/update frequency without redundancy. Every sentence contributes value, earning a top score.

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 zero-parameter tool with no output schema, the description fully explains what data is returned, provides a concrete example, notes the update cadence and source, and gives clear use-case scenarios. This is complete for the agent to invoke and interpret the result appropriately.

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?

There are zero parameters, so schema coverage is trivially 100%. The description compensates by explaining what the tool returns (GDP growth, inflation, current account balance by country group) and gives an example of the data format, which adds meaning beyond the empty 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 clearly states a specific action ('Returns IMF WEO macro composites') and identifies the resource (IMF WEO) and the specific metrics (GDP growth, inflation, current account balance by country group). It distinguishes itself from sibling tools by focusing on global macro context and country-group aggregates, which is unique among the listed benchmarks.

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 description explicitly specifies when to use the tool: 'when providing global macro context for an international expansion brief, country risk assessment, or board-level economic outlook presentation.' It does not mention alternatives or exclusions, but the use cases are clearly identified, giving the agent strong guidance on appropriate invocation.

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