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

Annotations already declare readOnlyHint=true and openWorldHint=false, and the description's only behavioral statement, 'Read-only,' simply restates them. It adds no context beyond the annotations — no behavior for an unrecognized id, no note about whether results are cached or complete.

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?

Two short, front-loaded sentences with zero filler: the action and scope come first, and the safety qualifier follows. Nothing could be removed without losing 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?

For a one-parameter read-only lookup with annotations covering safety and no output schema, the essentials are present, but routing against search_products and any statement about invalid-id behavior are absent. It is adequate but leaves obvious gaps an agent would have to resolve by trial.

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 0% for the single 'id' parameter, so the description carries the burden but contributes only 'by id'. The schema's enum of 23 valid product slugs compensates by fully enumerating legal values, but the description adds no format or sourcing guidance (e.g., that ids are catalog slugs).

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?

States a specific verb (Get), resource (Agent Field Kit product), and scope (one, by id), which implicitly separates it from the sibling search_products. It never names that sibling, but an agent can still tell this is a direct identifier lookup rather than a search.

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 only implied by the phrase 'by id' — the agent must infer that this is the tool for fetching a known product while search_products handles discovery. No explicit when-to-use, prerequisites, or error handling for an unknown id are given.

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