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

Annotations already declare readOnlyHint=true, idempotentHint=true, destructiveHint=false, and openWorldHint=false, so the parenthetical '(read-only)' merely repeats structured data. The description adds nothing about behavior beyond that — no not-found handling, no rate limits, no indication of how fresh the 'snapshot' is.

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 front-loaded sentence with the resource and key stated first. It is tight, though the trailing '(read-only)' parenthetical is redundant against the annotations and could be dropped.

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?

There is no output schema, so the description is the only place to describe what a 'company snapshot' returns, and it does not — the agent cannot tell which fields come back or how missing companies are signaled. For a single-parameter read tool this is adequate but leaves a real gap.

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 the parameter already documents the 8-digit pattern, an example (Novo Nordisk), and where to obtain the value. The description restates '8-digit CVR number' without adding format or sourcing detail beyond the schema, so baseline 3 applies.

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+key ('Get one company snapshot by 8-digit CVR number'), so an agent knows exactly what is retrieved and by what key. It does not, however, distinguish itself from siblings like search_companies or get_financials, leaving the differentiation to the schema text.

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 no when-to-use guidance and never names an alternative. With siblings such as search_companies (find companies) and get_financials (company financials) in scope, the agent gets no help deciding between a single-company lookup and a search or a financials call.

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