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

The annotations already declare readOnly, openWorld, idempotent, and non-destructive, so safety is covered. The description adds value beyond that by disclosing the response contract (short answer plus numbered sources) and that answers are truncated to the goal rather than truncated arbitrarily, which tells the agent how to interpret output length.

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 short sentences: purpose, return shape, usage trigger. Zero filler, and the answer-format detail is placed before the routing guidance so the agent reads the most load-bearing facts first.

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 correctly fills that gap by stating the return shape (short answer with numbered sources). With rich annotations and a fully documented two-parameter schema, the only real omission is sibling differentiation, which keeps it from a 5.

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% and both parameters carry their own descriptions, so the schema does the work. The description adds no field-level guidance (e.g., how to phrase the question, or when to raise max_tokens), so it neither compensates nor detracts — the 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?

The description gives a specific verb and resource (answer a question from the web) plus the return shape (short answer with numbered sources), so the agent knows this is a Q&A-over-web tool rather than a fetch tool. However, it never distinguishes itself from close siblings such as web_research or web_investigate, which plausibly overlap in purpose.

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?

"Use it for facts you do not know or that may have changed" gives a clear selection condition tied to knowledge gaps and recency. It stops short of naming when NOT to use it or which sibling (web_research, web_investigate) to prefer for deeper investigations.

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