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

Annotations already cover the safety profile (readOnly, non-destructive, closed-world), so the description's added value is in data-fidelity behavior: values are as captured, unstated fields become null and appear in a 'missing' list, and trial/seat model are quoted from notes. That is genuinely useful beyond the annotations, though nothing is said about what happens when a capture is stale or a product has no pricing page.

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?

The lead clause front-loads what the tool produces and its cardinality bound, and the second sentence handles edge behavior. The middle field enumeration is a long comma run that partly duplicates the output schema, so it is dense rather than wasteful.

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 an output schema present, the field-by-field listing is largely redundant, but the description does cover the fidelity/null contract an agent needs before calling. The missing piece is the relationship between the two input parameters, which neither the description nor the schema resolves.

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 parameter descriptions already explain the comma-separated id format and point to search_screens. The description adds only the '2 to 8' cardinality, and never clarifies whether screens and products are alternatives, combinable, or either-or — the single most consequential semantic for this tool.

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 names the exact resource (captured pricing pages) and the output shape (a fact table of 2 to 8 pages), which separates it from visual-diff siblings like compare_screens and from build-oriented tools such as build_handoff. It stops short of an explicit verb ('compares'), but the resource-plus-output framing is specific enough for selection.

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?

'For research rather than building' and the 2-to-8 page bound give implied usage context and a scope limit. However, no sibling is named — it never says when to prefer compare_screens, pick_reference, or get_product instead, and the choice between the two input modes is left to inference.

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