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

Annotations already cover the safety profile (readOnly, idempotent, non-destructive, openWorld), and the description goes well beyond them: it discloses the default tier, that only the requested tier is returned, that solutions may include clip moments, that missing tiers yield hint_unavailable, and that nothing is generated. This is rich behavioral context an agent cannot get from 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?

Four tight sentences with the core action and scope front-loaded, followed by default, return contents, and the hint_unavailable edge case. Dense but each sentence contributes; only minor redundancy between the tier enumeration and the default statement.

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?

With no output schema, the description does the work of describing return contents (tier, source links, evidence limitations, clip moments) and the hint_unavailable outcome. The only notable gap is the unexplained url parameter.

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 0%, so the description must carry parameter meaning. It explains the tier enum values and default, but says nothing about the required 'url' parameter (e.g., that it is the published guide URL), leaving one of two parameters undocumented in both schema and description.

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 states a specific verb and resource ('Retrieve exactly one authored tier for a published kingy.wiki guide') and narrows scope to a single tier, which separates it from get_guide (whole guide) and list/search siblings. An agent can tell what it fetches 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?

The description implies the use case (fetch one authored tier, default hint_1) but never names an alternative such as get_guide or states when this tool is preferred over it. Usage is inferable from the scoping language rather than explicitly routed.

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