getSectorPESnapshot

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

Annotations already establish that this is a read-only, idempotent, open-world operation. The description adds that the result is a snapshot of sector P/E ratios, but it does not explain freshness, the significance of the required date, or the response shape beyond the basic metric.

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 compact sentences, with the core retrieval purpose front-loaded. The use case follows clearly, though the explicit API name is slightly redundant and could be dropped without losing meaning.

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 read-only snapshot tool with complete schema descriptions and safety annotations, the definition is largely sufficient. It still lacks guidance on choosing between sector, industry, and historical P/E tools, which matters given the crowded sibling set.

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%, so the date, sector, and exchange parameters are already documented in the input schema. The description does not add any parameter-specific meaning beyond what the schema provides, which fits the baseline 3 when the schema handles the detail.

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: retrieve P/E ratios for sectors. It does not differentiate this tool from close siblings such as getIndustryPESnapshot or getHistoricalSectorPE, so it stops short of a 5.

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 use case—comparing valuation levels across sectors—but never says when to choose this over the industry or historical P/E siblings. It provides context, but no explicit routing or exclusions.

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