list_indexed_companies

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

With no annotations, the description carries the burden of behavioral disclosure. It mentions it returns a list and specifies the return fields, but it does not explicitly state that it is a safe read-only operation, nor does it describe edge cases like sorting, pagination, or exact limit enforcement. Some context is added, but not comprehensive.

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 concise and well-structured, starting with a clear one-sentence purpose, followed by Args and Returns sections. Every line provides useful information without redundancy, making it easy to scan.

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 tool with two optional parameters and an existing output schema, the description covers the core purpose and parameter semantics. However, it omits any usage guidance and does not mention behavioral limitations, making it slightly incomplete for an agent that must rely solely on this text.

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 description adds rich meaning beyond the bare input schema. It explains that query is a partial-match filter on company name and that omitting it returns all companies, and that limit sets the maximum number of items. This is exactly what the schema lacks, making parameters self-explanatory.

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 clearly states the tool retrieves a list of indexed companies ('インデックス済み企業の一覧を取得します'), with a specific verb ('取得') and resource ('一覧'). It is distinct from sibling tools like search_filings and compare_sections by focusing on listing companies.

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 provides no explicit guidance on when to use this tool versus alternatives. It only explains the function and parameters, leaving usage context implied. No exclusions, prerequisite steps, or alternative scenarios are mentioned.

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