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 covered. The description adds genuine behavioural substance by enumerating the five scoring components (accruals, cash conversion, working capital, persistence, capital intensity) and the resulting scale, which tells the agent what the output actually represents. No auth, rate-limit, or freshness/staleness disclosure, hence not a 5.

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?

Front-loaded with purpose, scale and scope before the component list and usage triggers. The five-component breakdown is dense but each clause maps to a distinct scoring input, so it largely earns its length; the single paragraph is slightly heavy for a one-parameter tool.

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?

An output schema exists, so return values need not be described. The description supplies everything else an agent needs: what the score means, its range, what drives it, and when to reach for it, which is complete for a single-parameter scoring tool.

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% and there is a single parameter, so the schema already documents the ticker format including examples. The description adds nothing about the ticker beyond what the schema states, so the baseline 3 applies.

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 verb and resource ('Get earnings quality score for an NZX company') and immediately defines the artifact as a 0-100 composite measuring how cash-backed and sustainable earnings are. This is clearly distinguishable from neighbours like get_accounting_quality or get_earnings by its explicit focus on cash-backing of reported profit.

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?

Gives three concrete when-to-use triggers: assessing whether profits are real cash vs accrual-driven, evaluating dividend sustainability, and filtering fair value models. It stops short of naming an alternative tool or stating when NOT to use it (e.g. vs get_accounting_quality), so it is strong context without explicit routing.

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