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

Annotations only cover read-only and open-world; the description goes well beyond them by disclosing cost (3 credits per call regardless of vertical or limit), that failed searches are free, the safe-retry/idempotency behavior, and the exact composition of the result set including answer boxes and related searches. That is the kind of behavioral context an agent needs to budget and sequence calls.

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?

Four tight sentences, each carrying distinct information: what comes back, vertical selection, limits/locale, cost, and the hand-off to scrape. The cost and failure-cost facts are stated early and nothing is padding.

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 takes on the burden of describing the return shape and does so concretely, plus covers pricing, retry safety, result caps and sibling routing. An agent has everything needed to call this 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?

Schema description coverage is 100%, so the schema already documents limit, query operators, country, language, vertical and idempotency_key. The description mostly restates these (default limit of 10, up to 100, country/language) rather than adding syntax or semantics beyond the schema, so baseline 3 applies.

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?

States a specific verb and resource ('Search Google and return the results') and immediately enumerates the return payload (titles, URLs, snippets, answer boxes, People Also Ask, related searches). It also names the sibling it is not ('use scrape to read a page'), so an agent can separate it from scrape/extract_* without opening any schema.

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?

Explicitly routes the agent away from this tool when full page content is needed ('Results are links and snippets: use scrape to read a page') and explains the vertical selector for web/news/videos. It gives clear context but no exclusions around when search is the wrong choice for entity/company lookups covered by company_profile.

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