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

Annotations already establish readOnlyHint=true and openWorldHint=true, so the safety profile is covered. The description adds genuinely new behavioral context: an explicit per-call cost ($0.005 USDC via x402) and per-indicator data provenance (IMF vs World Bank vs ECB), which materially affects whether an agent should call this or a free sibling.

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?

A single dense sentence that front-loads the resource and indicator coverage, then appends provenance and cost. Every clause carries information; it is long but not padded, and the cost detail is placed last where it is easy to find.

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 data-retrieval tool with no output schema, the description lists available indicators but says nothing about the return shape, units, or how results are keyed by year. The cost note and source attribution are helpful, but the missing explanation of from/to and output format leaves a real gap.

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?

At 50% schema coverage, the schema documents 'country' (ISO code) and 'indicators' (comma list) while the description adds useful provenance mapping (e.g., interest rates/exports/FDI from World Bank, policy rate from ECB). However, the 'from'/'to' parameters are undocumented in both schema and description, and the description never says they are years or how the range behaves.

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 resource (macroeconomic indicators), enumerates the core indicators, and names the data sources (IMF WEO with forecasts, World Bank, ECB), so an agent knows exactly what domain this tool covers. The phrase 'for any country' implicitly contrasts it with the US-scoped sibling macro_us, though it never names that sibling.

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?

Usage is only implied: 'for any country' suggests this is the general-purpose macro tool versus country-specific siblings like macro_us or labor, and the mention of forecasts hints at forward-looking use. There is no explicit when-to-use/when-not-to-use statement or named alternative, so the agent must infer routing.

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