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

Annotations already declare readOnly, openWorld, idempotent, and non-destructive behavior. The description adds useful context beyond those: data source (IMF DataMapper), license (CC BY 4.0), no auth required, and the inclusion of forward projections—a behavioral nuance that matters since years extend to 2035. No contradiction 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?

Three tight sentences: purpose and metric first, then filter behavior, then data source/license/auth. Every sentence earns its place, and the most decision-relevant information is front-loaded. 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?

With an output schema present, return format need not be explained. The description covers units (percent of GDP), data source, scope (countries/aggregates), filtering options, projection behavior, licensing, and authentication. An agent has everything needed to select and invoke the tool correctly.

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%, so the baseline is 3. The description mostly restates what the schema already says (e.g., omit country to return all countries plus aggregates, year range includes projections) and adds no new format or syntax details. It is consistent but does not materially enhance parameter understanding.

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 opens with a specific verb and resource: "Get current account balance (percent of GDP) from the IMF World Economic Outlook (WEO) for one or more countries, including IMF forward projections." This precisely identifies what the tool does and clearly distinguishes it from sibling imf.macro tools (gdp_growth, inflation, fiscal_balance) without needing to inspect schemas.

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 gives clear operational guidance: filter by ISO alpha-3 country code(s) and/or year range, or omit filters to get all 190+ countries plus regional/income-group aggregates. However, it does not explicitly state when to prefer this tool over sibling imf.macro tools or when not to use it, so it lacks explicit exclusions/alternatives.

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