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

Annotations already declare readOnlyHint, idempotentHint, destructiveHint=false, and openWorldHint=false, so safety and determinism are covered structurally. The description adds genuinely useful curation semantics — editor-approved only, unreviewed AI findings excluded, stable comparison_id — which an agent cannot get from annotations. It stops short of describing result volume or what an empty response means.

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 tight sentences, front-loaded with what is returned and filtered to why the results are trustworthy, ending with the follow-up handle. No filler or restatement of the tool name.

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?

An output schema exists, so return-value detail is correctly omitted, and the description covers the key conceptual distinction (curated vs. unreviewed) plus follow-up path. What is missing is only minor: behavior on no matches and the effect of the limit cap on result completeness.

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 75%, with brand, query, and retailer documented in-schema; only limit lacks a description but carries min/max bounds. The description adds no parameter-level meaning, but the baseline of 3 is exceeded only slightly given the strong schema — it is neither harmful nor additive, so a 3 would also be defensible; the low param count and optional nature justify a modest lift.

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 a specific verb-like scope ('published price comparisons built and reviewed by editors'), the exact unit of comparison ('one exact product (model, kit, condition) compared across retailers'), and explicitly distinguishes itself from get_comparison by noting that each result carries a comparison_id for that tool. An agent can tell what this retrieval returns without opening the 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?

Usage is implied rather than stated: search here to find comparisons, then fetch details with get_comparison (explicitly named). It also clarifies that only editor-approved offers are returned. However, it gives no guidance on when to prefer this over the sibling search_deals, nor any exclusion or fallback behavior (e.g., zero results).

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