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

Beyond the readOnlyHint annotation, the description discloses important batch behavior: results follow request order, unknown symbols return found=false instead of failing, dividend yield uses forecast dividends when available, and capped progressive dividend years are represented as "N or more". These details materially affect how an agent interprets and trusts the results.

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 front-loaded with the core purpose and the preferred alternative, followed by relevant return and formatting details. It is somewhat long because the English content is largely duplicated in Japanese, but the structure remains clear and the extra details are not filler.

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 no output schema, the description does a good job naming the returned metrics, preserving request order, and explaining the found=false sentinel. It references get_key_metrics_latest for the exact field set, which is useful, though the precise response envelope shape is not spelled out.

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?

The input schema already fully documents the single symbols parameter as comma-separated 4-digit ticker codes with a max of 50, so the description does not need to repeat syntax. It does add useful input-related semantics by stating that request order is preserved and unknown symbols return found=false rather than causing failure.

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 states a specific batch operation: latest PER, PBR, dividend yield, dividend, streak, and 3y/5y CAGRs for up to 50 companies in one call. It explicitly names get_key_metrics_latest and clarifies that this is the batch equivalent, making it distinguishable from the single-company sibling.

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?

It gives explicit guidance to prefer this over repeated get_key_metrics_latest calls when comparing or screening a list. It also explains how missing symbols behave, removing ambiguity about whether an unknown ticker aborts the batch.

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