What each catalogue answers

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

The description adds valuable context beyond the readOnlyHint: it states 'Reaches no catalogue,' clarifying that the tool performs no network calls to external sources. It also explains that the key-holding fact is local and does not affect catalogue behavior, which is useful behavioral transparency.

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, front-loads the purpose, and every sentence adds value. The second sentence clarifies an important nuance about key holding without being verbose.

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 zero-parameter tool with an output schema, the description covers the semantic meaning of the data (what catalogues answer, reading date, location of configuration facts) and explicitly states it reaches no catalogue. This is complete for the tool's 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?

The tool has zero parameters, and the description explicitly confirms 'takes no argument.' While there's no parameter detail to add, this meets the baseline for a zero-parameter tool.

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 clearly states what the tool does: it reports what each configured stash-box catalogue was measured answering and the date its surface was read. This is distinct from the sibling search/get tools, which operate on specific entities. The verb and resource are evident.

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 implies usage (e.g., to inspect catalogue capabilities and reading dates) but does not explicitly say when to use this tool versus alternatives. It mentions 'Reaches no catalogue' which hints at safety but lacks explicit exclusions or alternative references.

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