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

Annotations cover readOnly/openWorld/idempotent, and the description adds substantial independent context: exact price ($0.005), USDC wallet charging, budget caps, and a prompt-injection warning that results are third-party data not instructions. That is unusually rich behavioral disclosure for a lookup tool.

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?

Three tightly packed sentences, front-loaded with purpose before cost and safety. No filler, and each clause carries distinct information.

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 tells the agent what comes back (inventors, CPC classes) and covers cost, payment, and safety. It omits result limits/pagination behavior, a minor gap for a lookup tool.

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 baseline is 3. The description echoes the search-vs-number duality but adds no syntax, format, or constraint detail beyond what the schema and its per-parameter descriptions already provide (e.g. confirm_over_cap is only explained in 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 a specific verb+resource ('search or fetch by number' of 'US patents (USPTO)') and even names the returned data (inventors, CPC classes). This clearly distinguishes it from siblings like company_lookup, court_opinions, or legislation_lookup.

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 implies two usage modes (keyword search vs fetch by number) that map to the q and patentNumber params, but it never names an alternative tool or states when NOT to use it. Usage is inferred rather than prescribed.

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