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

With no annotations, the description carries the full burden and does well: it discloses the explanation components, describes logging behavior, privacy practices, and data retention. It does not explicitly state read-only side effects, auth needs, rate limits, or error behavior, preventing 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?

The purpose is front-loaded, but the first sentence is a dense enumeration and the logging paragraph is long. The logging/privacy details are relevant transparency, but the overall definition is wordier than necessary for invocation guidance.

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 complex tool with no output schema and no annotations, the description covers the main explanation outputs and logging/privacy context. It still lacks exact return format and error behavior, but it is substantially complete enough to call correctly.

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 compensate. It gives examples of accepted structure representations ('XYZ text or {Z|symbols, R}'), which helps, but does not clarify the schema's anyOf alternatives (string, array, or object) or required format details.

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+resource: 'Explain why Fittest trusted or escalated ONE structure,' and enumerates the explanation contents. It is clear what the tool does, though the sibling differentiation from check_structures is only implied by 'ONE structure' rather than explicitly contrasted.

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?

Usage is implied: use this to explain a single structure, versus likely batch checking in check_structures. However, there is no explicit when-to-use/when-not-to-use guidance or named alternatives, so the agent must infer the routing.

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