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

Annotations already declare the tool as read-only, idempotent, non-destructive, and closed-world. The description adds useful behavioral context beyond annotations: reports are quality-gated, each percentage includes its formula and report basis, and null values have a specific meaning. It does not discuss rate limits or data freshness, but the added transparency is substantial.

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, front-loads the core resource and ratio families, then adds important null semantics and exclusions. Every sentence contributes useful information without repetition.

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 description covers what the tool returns and how nulls should be interpreted, and annotations cover the safety profile. However, with no output schema and 0% schema description coverage, the missing parameter explanations leave the agent without enough information to confidently supply symbol and quartersBack.

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 0%, and the description does not explain either parameter. It does not state that symbol is required or whether it is a ticker/identifier, and it does not describe quartersBack, its default of 8, or its allowed range of 1–20.

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 names a specific resource and scope: quarterly financial ratios for a GPW company, including margins and equity/assets. It lists the exact ratio families covered and explicitly excludes price-based multiples and TTM estimates, though it does not directly differentiate itself from the sibling get_quarterly_kpis.

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 an implied usage boundary by excluding price-based valuation multiples and TTM estimates, which helps an agent know this is not a valuation-multiple tool. However, it does not explicitly say when to use this tool versus get_quarterly_kpis, get_public_price_history, or other siblings.

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