Fetch several pages

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

Beyond the annotations (readOnly/openWorld/non-idempotent), it discloses concurrency behavior, that fetches run 'under the account rate limit', and critically that a single failing URL does not fail the call but is 'reported in place'. That partial-failure contract materially changes how an agent should interpret results and cannot be inferred from the schema.

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?

Front-loaded with the core capability and size limits, followed by the failure/rate-limit contract and routing advice, with no filler. The second paragraph opens with a sentence fragment and an awkward mid-sentence line break, which slightly hurts readability but not substance.

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?

No output schema exists, yet the description covers the return shape (Markdown per page), the failure semantics, batch bounds and when to choose it over siblings. For a simple 3-parameter read-only tool, nothing an agent needs to call it correctly is missing.

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 `urls` (1-10 absolute URLs, bare hosts accepted), `max_chars` (0 disables cap) and `response_format`. The description only restates the batch cap and Markdown default, adding no syntax or semantics beyond the structured fields.

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 ('Fetch up to 10 web pages in one call and return each as Markdown'), including the hard batch limit and output format. It is clearly distinguishable from the sibling `fetch` (single) and `search` (discovery) tools.

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 says to 'prefer this over several `fetch` calls when you already know which URLs you need', naming the alternative and the selecting condition. The parenthetical example (top three search results) makes the intended `search` -> `fetch_many` workflow concrete.

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