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

Annotations already cover safety (readOnlyHint=true, destructiveHint=false) and open-world behavior. The description adds meaningful behavioral context beyond annotations: it discloses the output as 'quick answers with canonical article URLs', tells the agent this is a search over a fixed set of 290+ guides, and signals that results are summaries rather than full articles. No contradiction with annotations.

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 sentence packs scope, content type, language coverage, and output format with zero filler. The most decision-relevant fact ('Search 290+ editorial guides') is front-loaded, and every clause earns its place.

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?

The description covers what the tool searches, which topics, which languages, and what it returns (answers with canonical URLs), which is enough for correct invocation given no output schema. It could additionally mention that it is limited to editorial guides rather than other content types, but the phrase 'editorial guides' and sibling names make this reasonably inferable.

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 parameters are already well documented in the input schema, including defaults and enum meanings. The description adds top-level context (topics, language availability, network sites) but does not deepen parameter semantics beyond what the schema provides. Baseline 3 is appropriate.

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 uses a specific verb ('Search') and a precise resource ('290+ editorial guides across the ITIN finance network'), and clearly scopes the domains (loans, mortgages, credit cards, credit scores) and languages (English and Spanish). This distinguishes it from siblings like get_guide (retrieval of a specific guide), faq_lookup (FAQ answers), and find_itin_lenders (lender discovery) without ambiguity.

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 the user needs to find relevant editorial guides on these finance topics, and its scope statement rules out FAQs or lender-specific searches. However, it does not explicitly name alternatives or state when not to use this tool, so an agent must infer the boundary from sibling names rather than being told directly.

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