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

Annotations already declare readOnly, idempotent, openWorld and non-destructive, so the safety profile is covered. The description adds valuable non-schema behavior: the $0.25 USDC cost via x402, which is critical for an agent deciding whether to call. It doesn't say anything about latency, data freshness, or what happens for a company with no facility data.

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?

Two sentences, front-loaded with the returned field list before use cases and price. The field enumeration is long but each item is informative; no filler or repetition of the title.

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 carries the return-value burden and does so by listing the profile fields, and it discloses cost. What's missing is any sense of response shape/format, pagination, or behavior on no-match for a paid call – modest gaps for a lookup 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 description coverage is 100% and both parameters are documented in-schema (lookup company name, optional language enum). The description adds only that lookup works 'for any company' and that pricing is the same in every language, which is mildly useful but doesn't deepen parameter semantics 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?

States a specific verb+resource ('Corporate facilities and real estate footprint for any company') and enumerates the contents (HQ, facility count, square footage, owned vs leased, openings/closures, work policy), so an agent knows precisely what data comes back. It doesn't explicitly distinguish itself from near-neighbors like interzoid_building_profile or interzoid_property_history, which would be needed for a 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?

Names concrete application contexts – 'commercial real estate prospecting, site selection, supply chain, and account research' – which gives clear when-to-use framing. There is no explicit when-not-to-use or named alternative among the 58 siblings, so it stops short of 5.

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