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

Beyond the annotations, it discloses meaningful behavior: reads live public-index data, returns dated XLSX/CSV files, handles up to 100 LEIs, and keeps invalid and duplicate rows in the report. These details materially help an agent understand the operation and its output.

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 and reasonably short, but the first sentence is repetitive and keyword-heavy with repeated 'lei lookup,' 'lei check,' and 'verify lei numbers.' It could be tightened 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?

With rich annotations, an output schema, and full schema coverage, the description provides enough context to call the tool correctly. It covers purpose, trigger conditions, output format, limits, renewal-date behavior, and invalid/duplicate handling.

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%, so the input schema already documents both the LEIs array and the optional renewal date. The description reinforces the 100-LEI limit and optional renewal date but adds no syntax or format detail beyond the schema.

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 verb and resource: verify LEI numbers, check renewal dates, and detect lapsed LEIs. It is distinguishable from find_leis_by_name and get_lei_parents by focusing on verification of supplied LEIs, but it does not explicitly name those siblings or clarify the boundary against a generic LEI lookup.

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 a clear trigger: use when the user wants an LEI lookup, check, or renewal-date verification. It also includes an explicit exclusion against legal or regulatory advice, though it does not name alternatives such as find_leis_by_name for name-based lookup.

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