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

Annotations already declare the safe read profile, and the description layers on what they cannot: the cost (2 credits), the expected result size ('Large'), and the exact failure mode — a tier_restricted refusal at no cost that must be reported to the user rather than as absent data. That last point is genuinely non-obvious agent guidance.

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?

Front-loaded with the resource scope before the cost and alternatives, and every sentence carries actionable content. It runs five dense clauses in a single block, so cost, size and the section-bundling advice compete for attention, but nothing is padding.

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 still conveys enough to call correctly: source coverage, expected volume, cost, and failure behavior. Return shape (case identifiers, dates, court names) is left implicit, which is a minor gap for a data-retrieval tool with no schema to fall back on.

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?

Only one parameter and the schema already documents the 8-digit CVR pattern, so the schema does the heavy lifting. The description still adds routing value by telling the caller how to obtain the CVR when only a company name is known, which is meaning 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 resource (civil court cases, decisions, orders, recalls, notices from 8 Danish authorities plus the Statstidende gazette) for exactly one Danish company, including matching under earlier names. That scope cleanly separates it from every sibling in the list, which cover financials, ownership, management and profile.

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 an explicit inclusion rule ('call it only when the user asks about legal or regulatory history'), a prerequisite path ('use search_companies first when you only have a name'), and a named cheaper alternative ('one get_company call with `sections`'). Both when-to-use and when-not-to-use are covered with the sibling tool named.

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