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

No annotations are provided, so the description carries the full burden. It discloses that the tool takes no arguments, transmits no context, and returns a different passage each time, implying statelessness and randomness. It doesn't describe any potential side effects or edge cases, but for a read-only random passage generator, this is adequate yet not deeply detailed.

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 description is extremely concise, with two short sentences. It front-loads the purpose and includes only essential information. Every word earns its place, making it highly efficient.

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?

Given zero parameters, no output schema, and a simple behavior, the description covers the key points: what it returns, that it's random, and when to call it. It doesn't elaborate on the nature of the passage or any potential failure modes, but for a tool of this simplicity, it is reasonably complete.

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 tool has 0 parameters, so schema coverage is trivially 100%. According to the rubric, baseline for 0 parameters is 4. The description adds no parameter details, but none are needed.

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 action ('Returns a short passage') and identifies the resource as a passage. It also notes the randomness ('A different passage each time'), which helps distinguish it from sibling tools like 'koan' that might return specific types of passages. However, it doesn't clarify the nature or source of the passage, leaving some 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?

It provides a usage condition ('Call it when running long or hot'), giving a clear context for when to use it. However, the phrasing is cryptic and doesn't explicitly mention alternatives or when not to use it. For a simple tool, this is minimal but present.

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