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

Annotations already declare read-only, idempotent, and non-destructive behavior, so the description does not need to restate safety. It adds useful dataset context such as record counts and coverage categories, but does not disclose additional behavioral traits like default year behavior, pagination, or result shape.

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?

Two front-loaded sentences: the first identifies the operation and scope, the second itemizes included data categories. The record counts add useful context even if not strictly necessary, and the text remains compact and 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?

For a simple two-parameter read-only tool with a full output schema and complete parameter descriptions, the definition is sufficient for correct tool selection. It does not explain optional-year semantics, but that is not critical given the schema and annotations.

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?

Both parameters are already described in the schema with 100% coverage, so the schema carries the parameter meaning. The description adds no detail about ticker format, year ranges, or how the optional year behaves, providing no parameter-level value 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?

States a specific action and resource: retrieving ESG data for an NZX company. The description enumerates emissions, diversity, safety, and reporting standards, which clearly distinguishes it from overlapping sibling getters like get_governance_scores or get_metrics.

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 implied context: this is the tool for ESG data for NZX issuers. However, it does not explicitly state when to choose it over overlapping siblings or provide exclusion criteria, leaving alternative selection to inference.

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