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

Annotations already declare readOnly, idempotent, non-destructive and closed-world, so safety is covered. The description adds real behavioral context beyond them: it spells out the returned content including the conditional 'design_md' available only 'for some sites', and clarifies that caveats are per-reference known limits. It does not say what happens with unknown or partially invalid ids, which is the main remaining gap.

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 action and id provenance are front-loaded in the first clause, with payload detail trailing. The field enumeration is dense but justified because there is no output schema. The final sentence restating caveats slightly repeats the earlier 'caveats' list item, a minor redundancy.

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?

With no output schema, the description carries the full burden of explaining returns, and it does so thoroughly, including the conditional design_md field. For a two-parameter read tool it is nearly complete; only error/partial-result handling for bad ids is left unaddressed.

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 100%, so the schema already documents both 'ids' (1-20) and the 'lang' enum with its default, giving a baseline of 3. The description adds the provenance meaning of ids (where to obtain them) but says nothing about 'lang' or the batching implication of the 1-20 bound.

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 ('Get full detail for ... references by id') and immediately disambiguates from siblings by naming the three tools that produce ids (search_references, similar_references, random_references). It also enumerates the payload, so an agent knows this is the detail-expansion step 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 parenthetical naming search_references, similar_references and random_references is explicit routing guidance: come here with ids harvested elsewhere. There is no explicit when-not guidance (e.g. don't call with ids from an unrelated collection, or the cap of 20 ids being a batching constraint), which keeps it short of a 5.

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