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

Annotations already declare readOnlyHint=true, destructiveHint=false, openWorldHint=false, so the safety profile is covered; the description goes well beyond it with caching cadence, the `retired: true` flag and why retired text is still returned, the silent/empty-answer semantics, and the validation failure mode for non-uuid ids. That is behavioural context an agent could not infer from the structured fields.

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?

The core guidance is front-loaded and the no-ids/with-ids split is easy to scan, but there is waste and noise: a stray fragment ('off.'), theatrical phrasing ('If this door is silent'), and guillemets around a log description. A shorter, cleaner statement of the same rules would serve the agent better.

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, read-only lookup with no output schema, the description supplies return shape (short lines vs. full text), the retired flag, the empty-result meaning, and the error case. Nothing an agent needs in order to call this 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?

Schema coverage is 100%, so the baseline is 3; the description still adds intent — three ids is prompt-sized while 50 is review-screen-sized — which tells the agent how to size the call, not just its limit. It also repeats the absent-vs-`validation_failed` distinction already present in the schema, so part of the value is duplication rather than new meaning.

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 concrete verb and resource: returns platform rules for the agent as short lines for a prompt, and it names no sibling because none overlaps — it is the only knowledge/rule tool in the list. The two modes (all active rules vs. full text by ids) are stated up front, so the agent knows exactly what it gets without opening the 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?

Explicit operating instructions: call once and cache by `rev`, re-read on a platform poke or when the fallback poll comes due, use no-`ids` for all active rules, use `ids` for full text including retired ones. It also covers the negative case — an empty answer is normal and must not change behaviour — which is exactly the when-not guidance agents need here.

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