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

Annotations already declare readOnlyHint, idempotentHint, destructiveHint=false and openWorldHint=false, so safety is covered. The description still adds useful behavior beyond that: the list is metadata-only, sorted newest first, and the AT backend enriches output with ``country`` and a prefixed ``company_id``.

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?

Purpose and read-only status are front-loaded in the first two lines, followed by a compact parameter note and a return summary. Every line adds information; there is no filler despite the multi-section layout.

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 single-param listing tool with an output schema present, the definition covers the id format, the geographic restriction, the alternative tool for DE ids, the ordering, and the downstream chaining. Nothing needed to call it correctly is missing.

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 0%, so the description carries the full burden, and it delivers: the required company_id accepts "AT:{fnr}" with bare FNR tolerated, and it warns that this is Austria-only. An agent can construct a valid id without guessing.

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 (chronology of a company's filing documents) plus ordering (newest first) and scope (metadata). It is clearly distinguishable from get_document (single document) and get_document_text (extracted text), which are named as the alternatives/follow-ups.

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?

Explicitly routes the agent: for Austrian filings use this tool with an "AT:{fnr}" id, while for the German official register abstract use get_document with a "DE:" id. It also tells the agent to feed a resulting document_ref to get_document_text, giving a clear when-to-use and how-to-chain picture.

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