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

Annotations already declare readOnly, idempotent, non-destructive and closed-world, so the safety profile needs no restating. The description adds genuinely new behavioral context: the buyback figure is conditional ("if we do"), so the agent knows that field may be absent, and the field inventory signals the response is a rich single-record payload. It does not mention error behavior for an unresolvable identifier.

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?

A single sentence, front-loaded with the core action and identifier forms before the field inventory. The trailing enumeration is dense and slightly run-on, but each item helps an agent decide whether this tool returns what it needs.

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 one fully documented parameter, an output schema, and complete annotations, the definition covers what an agent needs to invoke it correctly. The only gap is routing guidance against the many product-related siblings.

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 the single parameter already lists id, slug, and full-URL forms with an example, so the description's mention of the same three forms adds no meaning beyond the schema. Baseline 3 applies.

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 and resource ("Full details for one product") and the three accepted identifier forms, so an agent can distinguish it from list/search siblings. It stops short of naming a sibling outright, so sibling differentiation is implied rather than stated.

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 "one product by id, slug or product URL", which narrows it to single-item lookups, but there is no explicit when-to-use statement nor guidance on when to prefer search_products, find_bullion, or get_buyback_price instead. Reference to a "price-history link" hints at get_price_history but does not route the agent there.

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