company_by_lei

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

No annotations are provided, so the description carries the full burden, and it does well: it discloses that values are derived, that the LEI field is withheld where the holder may be a natural person, that the registry does not validate LEIs, and that historical years may reflect a prior operator. It omits any note on auth or result size limits, but for a read-only lookup this is solid.

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?

A single dense paragraph that is front-loaded with the core purpose before the caveats and parameter behavior. Every sentence carries information, though it is packed tightly and could be broken up for scannability.

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 must describe returns, and it does: latest verified emissions plus yearly totals for verified emissions, free allocation and surrendered units, with the derived nature flagged. Combined with the data-quality caveats, an agent has what it needs to call and interpret this tool.

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 already 100%, but the description still adds meaning: LEI must be 20 characters with dashes/spaces ignored, detail=true adds each installation's years, and from_year/to_year bound the year range. This goes beyond the schema's terse field descriptions.

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+resource: returning all installations whose current Union Registry account holder registered a given LEI, along with their emissions data. The scope is precise and unambiguous. It does not explicitly contrast itself with the sibling search_installations, so it lands at 4 rather than 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?

Gives genuine usage context: 'no match does not prove the company holds no installation' because only ~a fifth of installations carry an LEI, and earlier years may belong to a previous operator. This tells the agent how to interpret results, though it never names alternative tools (e.g. search_installations) for the case where an LEI lookup fails.

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