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

Annotations already declare readOnlyHint=true and idempotentHint=true, so safety is covered. The description adds behavioral context beyond annotations: 'context is used to tailor the guide' and the session-level loading instruction, explaining how the tool behaves in use. No contradiction with annotations.

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?

First sentence states purpose, second gives usage timing, and the bullet list is scannable. The final paragraph about context overlaps with schema but adds a concrete instruction. It's longer than minimal but well-structured and front-loaded.

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 read-only reference tool with annotations and an output schema, the description covers what, when, all topic values, and context construction. Nothing needed to invoke 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?

The schema describes 'topic' only as 'Guide topic to read', while the description gives 11 bullets explaining exactly which use cases each topic covers. For 'context', it adds a first-sentence requirement beyond the schema's already detailed instrctions. With 100% schema coverage, this extra guidance clearly raises the score.

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 opens with a specific verb and resource: 'Read Done Bear's guide for one topic' and explains what the guide contains (what the data means, relation to product, how to use it). The bullet list clearly disambiguishes this reference tool from the operational siblings by mapping topics to concrete task types. No tautology or ambiguity.

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?

Gives an explicit trigger: 'Load a topic before doing that kind of work for the first time in a session.' This tells the agent when to call. It doesn't name alternatives or exclusions, but the tool's unique role among siblings makes that unneeded.

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