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

Annotations already declare readOnlyHint, idempotentHint, openWorldHint and destructiveHint=false, so the safety profile is covered. The description still adds genuinely new context: a per-call price with a free tier ('$0.005/call after 5 free/day'), the jurisdictional coverage scope, and the notion of deterministic resolution plus paid-source fallback. It stops short of describing latency or failure behavior when a registry is unavailable.

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?

Three compact sentences, front-loaded with the core capability before coverage, inputs, and price. The long parenthetical jurisdiction list is somewhat marketing-flavored but does convey real scope, so nothing is egregiously wasteful.

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 an output schema present, return values need not be explained, and the description covers scope, input modes, coverage regions, and cost. The main remaining gap is operational guidance for a free-tier-limited, paid-fallback tool in a family of overlapping resolver and verification tools.

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 every one of the eight parameters is already documented in the schema, including the identifier formats, the country/jurisdiction alias, and the sanctions default. The description only restates the accepted query types and the optional ISO country code, adding no new syntax or precedence rules; 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?

The description opens with a specific verb and resource ('Resolves official national corporate registry records, company status, and business identifiers') and names the accepted input forms, so the agent knows exactly what class of operation this is. It does not, however, distinguish itself from overlapping siblings such as screen_sanctions or verify_eu_vat, which it partially duplicates via the checkSanctions and verifyVat flags.

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?

'Accepts company names, domains, or national registration numbers with optional ISO country code' implies when the tool applies, and 'deterministic' hints at the non-fuzzy matching use case. But there is no explicit when-to-use/when-not guidance and no routing to the obvious alternatives (batch_resolve for volume, verify_eu_vat for standalone VAT checks, screen_sanctions for dedicated screening), leaving the agent to infer selection.

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