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

Annotations already mark this as read-only, idempotent, and non-destructive. The description adds meaningful behavioral detail beyond those hints: it revalidates current price/orderability, never performs fuzzy substitution, and returns a 'safe not-found result for ineligible items.' This clarifies error/eligibility behavior that annotations do not convey.

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 description is two sentences with no filler. It front-loads the core action and scope ('Revalidates one exact public catalog handle'), then adds the important behavioral qualifiers about fuzzy substitution and not-found handling. Every sentence contributes useful information.

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?

This is a simple single-parameter, read-only lookup tool with an output schema and strong annotations. The description covers the key semantics: exact handle, current price/orderability, checkout-policy context, no fuzzy matching, and safe not-found behavior. Nothing essential for calling it 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?

The schema already documents the only parameter as 'Exact public catalog handle,' so schema description coverage is 100%. The description reinforces the exactness with 'one exact public catalog handle' and 'never fuzzy-substitutes,' but it does not add substantial new parameter semantics beyond what the schema already provides.

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 states a specific verb and resource: it 'revalidates one exact public catalog handle' and checks 'current price and orderability.' It also clearly distinguishes itself from fuzzy lookup tools by saying it 'never fuzzy-substitutes,' which separates it from siblings like search_lab_catalog.

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?

The description gives clear usage context: use this tool when you have one exact public catalog handle and need a fresh price/orderability check under checkout policy. It does not explicitly name sibling alternatives or provide a 'when not to use' list, but the exact-handle and no-fuzzy-substitution language effectively excludes fuzzy-search use cases.

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