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

Annotations already establish read-only/idempotent safety, so the description earns credit for adding substantive behavior: data source is the latest financial statement with period ending 2025+, currency of book values (PLN/EUR/USD), and the null/no-breakdown condition for micro and small entities.

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 sentence, but front-loaded with the primary resource and its contents; the coverage caveat is appended as a parenthetical clause. Every element carries information, though the sentence is long enough to be slightly unwieldy.

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, but the description compensates by enumerating the returned fields (land, buildings, investment property, book values, collateral addresses/KW numbers/creditor). For a single-company lookup tool this is nearly complete, with only minor gaps such as exact field naming.

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 schema already documents krs, nip, and name. The description adds only the note that the record is 'keyed by KRS', providing marginally more meaning than the schema without covering the lookup-by-NIP/name fallback paths.

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 (company real estate) and enumerates exactly what data is returned: land incl. perpetual usufruct, buildings/premises, investment property book values, and mortgage-collateral locations. This makes it clearly distinguishable from siblings like get_company_financials or get_company_secured_liabilities.

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 usage context by naming the key (KRS) and the coverage boundary (null when the balance sheet shows no real estate; micro and small entities have no breakdown), which tells the agent when to expect empty results. It does not, however, explicitly route the agent against a specific alternative sibling.

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