emoji_lookup

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

Annotations already declare readOnlyHint, idempotentHint, openWorldHint, and destructiveHint=false, so the safety profile is covered. The description adds nothing beyond that: no match behavior (exact vs partial vs alias), no result shape, no rate/limit context. Acceptable but thin given annotations do the heavy lifting.

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?

One short sentence, front-loaded and waste-free. It is terse to the point of under-specification, which keeps it just below a 5.

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 read-only lookup with full schema coverage and annotations, the essentials are present. But with no output schema, the agent gets no indication of what is returned (emoji characters, names, unicode codepoints), which is a real gap for a lookup tool.

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% and the single parameter already carries examples ('heart, fire, smile'), so per the calibration rule the baseline is 3. The description adds no matching semantics (substring vs exact, case sensitivity) beyond the schema.

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?

Specific verb+resource ('Search emojis') with the lookup dimension (name or keyword) stated. It does not, however, distinguish itself from sibling emoji/data tools like emojihub_random, emojihub_by_category, or github_emojis, so the agent must infer the boundary.

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?

No explicit when-to-use or when-not-to-use guidance is given; the query example implies keyword lookup but the description never says how this differs from the other emoji siblings or what to do with an empty result.

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