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

The description adds useful behavioral context beyond the annotations: the dictionary is "living" (content changes over time) and covers dialect variants and tonal diacritics, so the agent knows results may be multi-variant. However, the annotations declare destructiveHint=true, readOnlyHint=false and openWorldHint=true for what is framed here as a pure lookup, and the description never addresses that gap, nor does it mention result limits or pagination. With annotations present the bar is lower, so a 3 reflects real but partial added context.

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 core action and followed by the routing rule; nothing is redundant. The example-word list is somewhat long, but each item is short and the list genuinely helps an agent match user queries to this tool, so it earns its space.

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 two-parameter lookup with no output schema, the description effectively previews the return payload (definitions, classifications, kinship titles, tone markings, dialect variants, example sentences), which is the main thing an agent needs before calling. It leaves the destructive/openWorld annotations and any result-size expectations unexplained, so it is complete but not airtight.

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 both parameters are already documented in the schema, and the description adds little parameter-level meaning. Only indirectly does it hint at schema semantics — the mention of tone marks and dialect variants aligns with the tone-optional `word` field and the `dialect` filter — but it never explains the dialect enumeration or fallback behavior when a dialect has no entry.

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 gives a specific verb and resource ("Search the living Igbo dictionary (Ọkọwa Okwu)") and enumerates the content it indexes: definitions, grammatical classifications, kinship titles, tonal diacritics, dialect variants, example sentences. That is far more informative than a restatement of the name. It does not explicitly contrast itself with the dictionary-adjacent siblings (lookup_name, search_proverbs, lookup_nsibidi), which keeps it just short of a 5.

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 states an explicit routing rule — "USE THIS FIRST for questions like 'what does [word] mean' or general Igbo vocabulary" — plus concrete query examples (ada, okpara, chi, mmiri). The word "general" implicitly carves out the specialized sibling lookups, but no sibling is named as an alternative, and no exclusion for proverb/name/nsibidi queries is spelled out.

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