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

Annotations already declare readOnlyHint, idempotentHint, non-destructive and closed-world, so the safety profile is fully covered by structured data. The description adds scope context (what is assessed) but, with an output schema present, the enumeration of return fields is largely redundant, and it discloses nothing about auth, rate limits, or error behavior.

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?

Purpose and scope are front-loaded in the first sentence and the usage triggers land last, which is good ordering. The third sentence re-lists return values already covered by the output schema, so some text does not fully earn its place.

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 handling return values, annotations covering safety, and a 100%-documented single parameter, the description supplies what remains: the framework identity, the assessment scope, and when to invoke it. Complete enough to call correctly, though sibling differentiation is implied rather than explicit.

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% for the single ticker parameter, including a format example, so the schema does the heavy lifting. The description adds no syntax or constraint detail beyond what the schema already states, making the baseline 3 appropriate.

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?

Specific verb (Get) plus a precise resource and scope: an NZ CS 1-3 gap analysis for an NZX company, broken into named categories with counts. An agent can distinguish this climate-specific compliance tool from siblings like get_esg_disclosure_gap or get_property_climate_risk without opening any schema.

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 final sentence gives explicit trigger conditions (climate compliance, NZ CS readiness, XRB requirements, TCFD gaps), which is strong context. It stops short of naming a contrasting tool or an exclusion, so it does not reach the 5 level of 'use X, not Y'.

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