faq_lookup

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

Annotations already declare readOnlyHint=true and destructiveHint=false, covering the safety profile. The description adds useful behavioral details not present in annotations: each answer includes its source article URL and the tool covers 1,800+ FAQs, which helps set expectations.

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 that captures the action, scope, languages, and output detail. It contains no wasted words and is highly scannable for an agent.

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 simple read-only search tool with two parameters and no output schema, this description provides all essential context: what it searches, the scope, language options, and a key output behavior (source URLs). It is sufficiently complete 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 describes lang with an enum and description, but query only has length constraints. The description compensates by clarifying that query should be a specific ITIN finance question, adding semantic meaning beyond the bare schema constraints.

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 clearly states the tool searches 1,800+ editorial FAQs for direct answers to specific ITIN finance questions. It distinguishes itself from sibling tools like search_guides by focusing on FAQs with direct answers, and mentions language options (EN/ES).

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 use when needing a direct answer to a specific ITIN finance question, and mentions language coverage. It doesn't explicitly list alternative tools or exclusion criteria, but the context is clear enough for an agent to infer appropriate use.

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