Hae kaupparekisterin muutokset (PRH)

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

Annotations already declare readOnlyHint, openWorldHint, and idempotentHint, covering safety and idempotency. The description adds that it uses PRH's open API and covers all trade register companies, which is useful context. It does not mention rate limits, error handling, or return format specifics, but given the annotations, this is acceptable.

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?

The description is two sentences, front-loaded with the primary purpose and examples, followed by input instructions. Every sentence earns its place; there is no fluff or redundant detail.

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?

For a read-only, idempotent tool with 2 parameters and no output schema, the description covers the input format, the types of changes returned, and the data source. It does not detail pagination or ordering, but the max_tulokset parameter handles limits. Missing error behavior is mitigated by the openWorldHint annotation.

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%: both parameters (hakusana and max_tulokset) have descriptive text. The description repeats the input format ('Anna Y-tunnus tai yrityksen nimi') but does not add new meaning beyond the schema. Since the schema already covers semantics, the description adds marginal value.

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 states a specific verb ('Hakee' - fetches) and resource ('yrityksen perustiedot ja aikajanan kaupparekisteriin rekisteröidyistä ilmoituksista' - company basic info and timeline of registered notices) and lists concrete change types (board/name changes, financial statements, share capital, bankruptcy). This clearly distinguishes it from the sibling hae_yritystiedot_prh, which presumably only retrieves basic company info.

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?

The description gives clear input guidance ('Anna Y-tunnus (1234567-8) tai yrityksen nimi') and states full coverage ('Täysi kattavuus kaikkiin kaupparekisteriyrityksiin'), providing context for when to use it. However, it does not explicitly mention when not to use it or point to alternative tools, so it stops short of explicit exclusions.

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