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

Annotations already cover read-only, idempotent, open-world and non-destructive traits, and the description still adds substantial behavior: per-fact source attribution with read dates, cross-checks between sources, swisstopo address validation only 'when published', and Zefix-derived register status with deletion dates. This is exactly the provenance/availability nuance annotations cannot express.

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?

Front-loaded with the verb and resource, then layered with data sources, coverage caveats and exclusions. Dense but every clause carries information; the parenthetical source names and 'when available' qualifiers are necessary rather than 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?

No output schema exists, so the description must convey what comes back — and it does: sourced facts, read dates, cross-checks, address validation and register status, plus an explicit list of what is not covered. An agent knows the response shape and limits before calling.

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?

Only one parameter and schema coverage is 100%, so the schema already documents uid fully. The description repeats the CHE-xxx.xxx.xxx format rather than adding syntax or validation detail beyond the schema, so the baseline 3 applies.

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 ('Look up a Swiss company by its UID') and enumerates the exact data domains returned (LINDAS commercial register, FINMA, GLEIF LEI, Zefix status), which differentiates it from siblings like finma_search or kyc_check without opening either schema.

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 clear scope boundaries and exclusions ('FOSC publications, SECO sanctions and officers are not covered'; 'No score'), which implicitly routes scoring-style needs to kyc_check. It stops short of explicitly naming the alternative tool or stating when this should be preferred over kyc_check.

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