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

Annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false, covering the safety profile. The description adds 'deterministic' and 'signed,' which are mildly useful behavioral traits not present in the annotations, but it does not clarify what 'signed' means or what the assessment returns.

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 short and front-loaded, but the brevity is under-specification rather than efficiency. It spends one clause restating the title and a second clause on a phrase so generic that it conveys little operational meaning.

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 the complex tool name, the large sibling context, and a required but undocumented 'candidates' parameter, the description is far from complete. An output schema exists, but the description still needs to explain the assessment basis, the shape of candidates, and when this selector is appropriate.

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 input schema requires 'candidates' but provides no property definitions, types, or constraints. The description never mentions 'candidates' or explains what shape the input should take, so an agent has no way to construct a valid call beyond guessing.

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 restates the tool name ('Service Failover Selector') and adds the vague phrase 'deterministic signed assessment over supplied input.' It does not explain what the selection is based on, what 'service failover' means in practice, or how this differs from sibling tools like payment_route_selector or try_service.

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?

No guidance is given about when to use this tool versus alternatives. The sibling list contains many selection and assessment tools, but the description never names a condition, prerequisite, or exclusion that would help an agent route to this tool.

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