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

Annotations only cover the safe-read profile (readOnly, idempotent, non-destructive); the description goes far beyond them, disclosing the return shape of `attributes`, the meaning of each `status` value, how to behave on conflicts ('tell the user they disagree'), that a retailer can appear under two values, and strict rules for treating specs.description as non-authoritative. This is unusually rich behavioral guidance.

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?

Purpose and scope are front-loaded, and nearly every sentence carries semantic payload (status meanings, conflict handling, description caveats). It is dense and long, but the length is largely justified by the absence of an output schema; only minor tightening is possible.

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, so the description carries the full burden of explaining return values — and it does: attributes structure, status semantics, specs.description caveats, plus pricing, availability, delivery time, and offers[].stock nullability. Nothing an agent needs to call and interpret this tool 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 coverage is 100% for the single required parameter, so the baseline is 3. The description adds real value on top: it states the tool 'Accepts both canonical product IDs and original retailer offer IDs,' which the schema's 'unique product ID from search results' does not convey.

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?

Opens with a specific verb+resource+scope: 'Get full details for a single product by ID.' It also names the sibling search_products and states the relationship ('Use this after search_products only for your final 1-3 picks'), so an agent can distinguish it from search without opening either 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?

Explicit when-to-use and when-not-to-use: only after search_products, only for the final 1-3 picks, and only when you need what search lacks (description-only details or all retailer offers/buy links). It even notes that search results already carry `attributes`, removing the main reason an agent might over-call this tool.

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