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

Annotations already declare it read-only and closed-world, so the description focuses on data semantics instead: two separate lists (`reasons` live, `retired` kept only for reading old feedback) and the label-vs-source_label distinction with the 'never translate from label' warning. It does not state caching lifetime or whether retired entries can appear in the live list, leaving minor gaps.

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 one short sentence, followed by ordered operational guidance. It is dense and includes downstream UI instructions (send `reason_shown_lang` with the rating) that belong to a different call, which is scope creep but each sentence still carries real information.

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?

There is no output schema, so the description must describe the return shape — and it does: the `reasons`/`retired` split, plus `label`, `lang`, `source_label`, `source_lang`, and `rev`. Given a single optional parameter and read-only annotations, nothing needed to call it correctly is missing.

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?

Only one parameter, `locale`, and the schema already documents the exact → base → English fallback chain at 100% coverage. The description never discusses the input parameter, instead explaining response-side fields (`lang`, `source_lang`), so it adds no meaning beyond the schema here.

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?

Opens with a specific verb+resource: returns the reason options a person can pick after rating the agent. It immediately distinguishes itself from sibling write tools like rate_agent_result or add_feedback_message by framing itself as a read-only dictionary lookup.

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?

Explicit invocation guidance: call once when the widget opens, cache the result, re-read only when the platform signals a dictionary change or lazily via `rev`. It also prescribes the degraded path — if the call returns nothing, still show the free-text field and count the rating.

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