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

readOnlyHint=true already tells the agent this is a safe read, so the description needn't restate it. 'Full details' adds a small amount of return-context in the absence of an output schema, but nothing is said about behavior on a missing/invalid id or what the detail payload contains.

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?

One sentence, zero waste, with the resource and the id-source front-loaded. 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 single-parameter read tool whose safety profile is already covered by annotations, the definition is nearly sufficient: it says what it returns (full details), keyed by what, and sourced from where. Only the shape of 'full details' and failure behavior are left implicit.

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. It does add meaning by telling the agent where the id comes from (search_catalog), but says nothing about id format or what happens with malformed values.

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 and resource ('Full details for one catalog item') plus the key it is fetched by ('by its id'). The parenthetical naming search_catalog makes clear this is the detail-fetch complement to that search tool, so an agent can distinguish it from the sibling 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?

The '(from search_catalog)' note implies the intended workflow — search first, then fetch details — which is genuine usage context. However, there is no explicit statement of when to use this versus the other siblings, and no exclusions or prerequisites are given.

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