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

Annotations already mark it as read-only and idempotent. The description adds meaningful behavioral context: it covers twenty registers, includes the provision the window comes from, and highlights the key minority case where opposition runs after registration. It does not describe the exact output format or fallback for unknown offices, but this is minor for a simple lookup.

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 front-loaded with a direct answer to the tool's purpose, followed by valuable domain context and input guidance. Every sentence contributes meaning, with no redundancy or filler.

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 one-parameter read-only lookup, the description covers purpose, the critical pre/post-registration distinction, input flexibility, and data coverage. The only notable gaps are lack of explicit return format and undefined behavior for offices not in the twenty registers, but overall it is sufficient for an agent to select and invoke the tool correctly.

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?

The schema only provides the parameter name 'office' with no description. The tool description fully compensates by specifying that it accepts a country name, an office name, or a two-letter code, and gives examples ('japan', 'JP', 'EU'). This adds essential 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?

The description states exactly what the tool does: it tells how long you have to oppose a filing in a trademark office and from when. It also uniquely differentiates itself by addressing the pre-registration vs post-registration opposition trap, making it clearly distinct from sibling tools.

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?

It provides clear context on when to use the tool: for any trademark office, and it warns against applying one office's rule to another. It also explains valid input forms. However, it does not explicitly name alternatives or state when not to use it, though the sibling names imply some differentiation.

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