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

Annotations already declare readOnlyHint=true and openWorldHint=false, so safety is covered. The description adds meaningful behavior beyond that: replies are localized to the poem's language, and with no output schema it previews what the payload contains (rules, tips, limits). It does not mention caching or format details, hence not a 5.

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 tight sentences: content summary first, usage directive second, language note last. No filler or repetition, though the closing sentence is a minor restatement of the schema's language note.

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, fully documented, read-only lookup tool with no output schema, the description covers purpose, timing, and return content adequately. An agent has everything needed to call it correctly on the first move.

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 enum already explains that each language has its own poem. The description only adds that replies also come in that language, which is output behavior rather than parameter syntax, so the baseline 3 for a fully documented schema applies.

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 (get the full rules) and enumerates the exact content returned: movement, legal lines, scoring, tips and limits. This is clearly distinguishable from siblings like read_poem, add_line, and leaderboard without opening any schema.

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?

"Read once before your first move" gives an explicit trigger condition for when to call this tool. It does not name alternative tools or state when not to use it, so it falls just short of the top band, but the usage context is unambiguous.

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