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

Annotations already declare readOnlyHint=false and destructiveHint=false, so the safety profile is covered. The description adds genuinely new behavior — 'Each item has its own status' signals per-item partial success/failure — but says nothing about execution order, concurrency, or how failed items are reported.

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?

Two short sentences, no filler, with the batch-size constraint front-loaded. It is efficient, though the second sentence is very terse and could carry more signal without becoming bloated.

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?

For a batch tool with a nested-array parameter and no output schema, the description should explain the per-item result shape it alludes to ('its own status') and what json_schema controls. Neither is covered, so an agent must guess at both input semantics and return structure.

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 0%; the nested 'url' and 'json_schema' fields are undocumented in both schema and description. The description confirms the 20-item cap already encoded as maxItems, but never explains that json_schema is the per-item extraction target schema, leaving the most consequential parameter opaque.

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 action and scope: running up to 20 extract calls in one batch, which implicitly distinguishes it from the single-call sibling 'extract'. It does not explicitly name a sibling for contrast, but the batch framing is unambiguous.

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?

Usage is implied by 'up to 20 extract calls' — an agent can infer this replaces N individual extract calls. However, there is no explicit when-to-use statement, no threshold below which single 'extract' is preferred, and no mention of sibling tools like explain_extractor.

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