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

readOnlyHint=true and openWorldHint=false already tell the agent this is a safe, non-open-world read, so the description's burden is reduced. The only added behavioral signal is 'Full details', which indicates a complete record rather than a summary — useful, but it says nothing about not-found behavior or what the response contains. Adequate but thin given the annotations already cover safety.

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 front-loaded sentence with no redundant wording; the resource, scope, and lookup key all appear immediately. Nothing is padded or repeated from the name.

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 tool with annotations covering safety and no output schema to explain, the description is close to sufficient. The remaining gap is the id's expected form and retrieval-failure behavior, which is minor at this complexity.

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%, so the schema says only that 'id' is a required string. The description compensates minimally by indicating the id identifies a catalogue item, but it supplies no format, source, or example for that identifier. With a single undocumented parameter the description should do more of the work than this.

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 of one catalogue item'), plus the lookup key ('by id'), which implicitly separates it from list/search siblings such as search_catalog or list_guides. It does not explicitly name an alternative, so it falls short of a 5, but an agent can tell this is a single-record fetch 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?

The phrase 'by id' implies the precondition that the caller already holds an item identifier, which is the main when-to-use signal. There is no explicit statement of when NOT to use it or a named alternative (e.g. use search_catalog when you only have a name), so guidance is implied rather than stated.

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