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

Annotations already declare readOnlyHint=true and idempotentHint=true, covering the safety profile. The description adds useful behavioral context beyond this: returns annual data sourced from World Bank, IMF, and UN, and explains the date-parameter omission behavior. This supplements rather than contradicts the 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 three tight sentences that front-load the purpose, then add metric examples, data provenance, and usage rules. Every sentence earns its place, and the pointer to a sibling discovery tool is a valuable addition without bloat.

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 read-only query tool with a rich input schema, a complete output schema, and safety annotations, the description covers all essential operational aspects: scope, valid metrics, data source, date-range semantics, and metric discovery. No critical calling information is missing.

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 description coverage is 100%, so the baseline is 3. The description adds metric key examples and reinforces the start_year/end_year omission behavior, but most of this information is already present in the input schema property descriptions. It does not add substantial meaning 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 opens with a specific verb-resource pair: "Query a specific economic indicator time series for an African country." It enumerates example metrics (GDP, inflation, unemployment, etc.), clearly scoping the tool to economic indicator data and distinguishing it from sibling Africa tools like africa.markets.fx_rates and africa.countries.list.

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 gives clear operational guidance: omit start_year/end_year for the latest value and supply both for a historical range. It also explicitly routes metric discovery to the sibling africa.countries.signals tool. However, it does not explicitly state when not to use this tool versus other Africa data tools, so it stops short of a full when/when-not set.

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