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

Annotations already cover the safety profile (readOnly, idempotent, closed-world), and the description adds real behavioral value by saying the result reports whether the corpus pairs the words, how strongly, and which words normally substitute. It stops short of describing thresholds or scoring semantics, but the essentials are disclosed.

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?

Three short sentences, question front-loaded, mode-specific details following, no filler. Every clause carries information about purpose, inputs, or output.

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 an output schema present the description needn't explain return values, and it still sketches them. Purpose and both input modes are covered; only edge behavior (both word and phrase set, limit semantics) is left implicit, which is a minor gap for a read-only checker.

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 80% and the schema already documents lang, word, phrase, and partner_pos, so the baseline is 3. The description reinforces the phrase/word mode split and gives a concrete phrase example, but adds nothing about limit or how the two input modes interact if both are supplied.

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 check — whether a word pairing is natural — and splits it into two concrete modes (two-word phrase vs. single word) with an illustrative example ('napraviti odluku' -> donijeti). That makes it distinguishable from lookup_word or get_forms, but it never explicitly contrasts itself with those siblings.

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 two usage contexts: pass a two-word phrase to validate collocation, or a single word to list its usual partners. The closing line 'Catches word-for-word translations' gives the motivating scenario, though it never says when to prefer a sibling tool instead.

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