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

With no annotations provided, the description carries full responsibility for behavioral disclosure. It adds the '20+ years' time span detail, but it does not explicitly state that the operation is read-only, does not mention response format, pagination, authentication needs, or error behavior. The verb 'get' implies a safe read, but the lack of explicit disclosure leaves significant gaps.

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 a single sentence, front-loaded with the core action and scope, and contains no redundant or filler text. Every word adds value, and it is highly scannable.

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?

The tool is relatively simple with only two parameters and a clear purpose, and the description covers the main functionality. However, it does not explain the return structure of the time series, nor does it clarify how to obtain valid indicator_id or country_id values, and it does not address potential overlap with get_series_data. These omissions leave some operational ambiguity.

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% (both parameters have descriptive comments). The description adds no new parameter-level semantics beyond what the schema already provides—it merely restates 'country and indicator pair,' which maps directly to the two parameters. Per the calibration baseline, a score of 3 is appropriate when the schema already documents all parameters.

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 verb ('Get'), a resource ('historical time series'), and a precise scope ('country and indicator pair', '20+ years'). This effectively distinguishes it from sibling tools like get_series_data by emphasizing the long time span, while also being immediately understandable.

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 conveys clear context: use this tool to retrieve historical time series for a specific country and indicator over 20+ years. It implies the appropriate scenario, though it does not explicitly mention alternative tools or any when-not-to-use conditions.

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