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

Annotations only declare readOnlyHint=false and destructiveHint=false; the description adds the substantive behavior: the returned link expires in 30 days, the worksheet is not saved and no PDF is produced, words are never silently removed, and the failure path returns unresolved_words/remainingWords/alternatives with reasons. This goes well beyond what the annotations convey.

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?

Purpose is front-loaded in the first sentence and every later sentence carries real information about the failure path. It is one dense unbroken block, though, and the error-handling detail could be tightened for faster scanning.

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 five parameters, a nested answers object, no output schema, and a non-idempotent creation behavior, the description covers both the success return (problem list shape, link lifetime) and the failure return (code, rejected words, alternatives). An agent has everything needed to invoke it and interpret either outcome.

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 grade limits, the 8–24 word bounds, title default, format enum, and the answers object are already documented. The description reinforces a few of these (answers only relevant for writing tests, elementary-kanji restriction) but adds little syntax or format detail beyond the schema; baseline 3 applies.

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 names a specific verb and resource (build an A4 kanji-test draft from an 8–24 word list, returning a problem list and a 30-day link) and scopes it (elementary school kanji only, no saving/PDF). It never distinguishes itself from the sibling create_kanji_worksheet, which a reader must assume is the non-word-list variant.

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 clearly states the operating condition (one unresolved word aborts the draft; the tool will not drop words on its own; remainingWords ≥ 8 means you can proceed) and tells the agent what the caller must decide. It gives no sibling-level routing guidance (e.g. when to prefer create_kanji_worksheet or find_kanji_words), which is the remaining gap.

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