web_search

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

With no annotations, the description carries the load and does disclose real behavioral facts: results are concise, contain titles/URLs/snippets, default to 5, and the query is passed through to a configurable backend so operator support is backend-dependent rather than guaranteed. It does not mention rate limits, auth, caching, or result ordering, which keeps it from a 5.

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 sentences, front-loaded with the action and return shape, then the sibling routing, then the query caveat. Every sentence carries distinct information with no restatement of the schema's min/max bounds.

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?

There is no output schema, and the description compensates by describing exactly what comes back (titles, URLs, snippets). With only two parameters, full schema coverage, and a stated default count, an agent has everything needed to invoke 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 coverage is 100%, so the baseline is 3, but the description adds genuine meaning beyond the schema by naming concrete operators (site:, filetype:, intitle:, -term, quotes) and flagging that support depends on the backend. That operator vocabulary is not present in the schema and directly affects how an agent should phrase a query.

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 the web") plus the return shape (titles, URLs, snippets) and default result count. It also names the sibling it is not ("Use web_extract to read a result in detail"), so an agent can route between the two without opening either 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?

The description explicitly routes detail-reading to web_extract, which gives clear conditional guidance for the one sibling that exists. It stops short of stating exclusions such as when searching is inappropriate or how to handle zero-result or rate-limited situations, so it falls short of a full 5.

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