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

Annotations already cover the safety profile (readOnly, idempotent, non-destructive, closed-world). The description adds genuine semantic context beyond that: it warns that the date intervals do not prove continuous coverage and are not historical existence dates, and it differentiates what is returned in each mode.

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?

Four compact sentences, front-loaded with what is listed, then the date caveat, then the two modes. Each sentence carries information; no filler, though the caveat sentence is fairly dense.

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?

An output schema exists, so return structure needn't be re-explained, and annotations cover safety. For a single-optional-parameter read tool the description supplies the key caveats (interval meaning) and mode behavior, leaving only minor gaps like sigla format.

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% (the single 'sigla' property is undocumented in the schema), so the description must carry the load. It does: it explains that 'sigla' is the abbreviation used in search and that providing it returns a single periodical's record, while omitting it broadens the listing. It stops short of giving the exact format of a valid sigla.

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 states a specific verb+resource (lists the periodicals held) and clearly spells out the two invocation modes: with 'sigla' it returns the single periodical's record, without it lists genre, periodicity and location. An agent understands the tool's scope, though no sibling (e.g. archive_info, search) is named to differentiate it.

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?

It explains the effect of supplying vs omitting 'sigla', which is real usage context, but gives no explicit when-to-use/when-not guidance and names no alternative tool for related lookups. Usage is implied rather than prescribed.

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