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

With no annotations provided, the description carries the full burden. It discloses the scope of data returned (dates and requirements per country) and that the Dynamics NAV lifecycle applies everywhere, which is useful. However, it does not disclose whether the tool performs live lookups, whether results are filtered by the optional current_erp parameter, or what happens when country='any' is used. These are gaps, but the description does add meaningful behavioral context beyond the schema.

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 a single, information-dense sentence that front-loads the core purpose and then lists coverage. It is efficient and every clause adds value. It could be slightly more structured (e.g., separating the coverage list from the behavior), but it is not bloated.

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 lookup tool with two optional parameters and no output schema, the description is largely complete: it states what is returned, for which countries, and that the NAV lifecycle is global. The main missing piece is how current_erp influences the results, but the tool is simple enough that this is a minor 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%, so the schema already documents both parameters. The description adds context by naming the countries and regulations, which helps an agent understand what values like 'ES' or 'PL' map to, but it does not explain how current_erp affects the results. Baseline 3 is appropriate since the schema does the heavy lifting.

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 ('Return') and resource ('compliance and platform deadlines'), and enumerates the exact countries and regulations covered (Spain's Verifactu, e-invoicing, DeCA, SII; Poland's KSeF; US tariffs and pharmaceutical duty; Dynamics NAV lifecycle). This clearly distinguishes it from sibling tools like check_deca_obligation or check_nav_support_status, which are narrower in scope.

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 implies when to use this tool: when you need compliance/platform deadlines by country. It names the covered countries and the Dynamics NAV lifecycle, which helps an agent choose it over more specific siblings like check_deca_obligation or check_nav_support_status. However, it does not explicitly state when NOT to use it or name alternatives, so it falls just short of a 5.

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