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

With no annotations, the description carries the full behavioral burden and does disclose real constraints: a 50-item batch ceiling, a 40-character per-item limit, and skip-on-duplicate semantics. It omits permissions requirements and whether the response reports skipped vs added items, which is the remaining gap for an unannotated mutation tool.

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?

Two sentences, front-loaded with the purpose and the destination, followed by the limits and dedupe behavior. Every clause carries information an agent would otherwise have to guess.

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, unannotated, no-output-schema write tool, the description covers purpose, limits, and idempotency. It stops short of describing what the call returns or how partial failures are reported, which would fully close the loop.

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 coverage is 0% — the single `words` array param has no description at all — so the description must compensate, and it does: it explains the array holds names/terms, its batch limit of 50, and the 40-character constraint per item. Only the item format (plain strings vs phrases) is left implicit.

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 — add names and terms to the user's dictation dictionary — and even names the exact settings location (Settings › Dictation). No sibling tool covers dictation vocabulary, and the description makes the scope unmistakable.

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?

Gives concrete examples of what belongs in the dictionary (people, companies, products, jargon), which tells an agent when this tool is the right call. There are no exclusions or stated alternatives, but none exist among the siblings, so the gap is minor.

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