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

Annotations already declare this read-only and non-destructive. The description adds behavioral detail beyond that: it always returns a per-operation routing plan with specific components (version, endpoint, auth, example) and will interactively ask clarifying questions when information is incomplete. This gives the agent a concrete sense of how the tool behaves at runtime.

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?

Three sentences with no filler. The first sentence states the core action and scope, the second specifies the mandatory output format, and the third sets the interaction rule. Everything earns its place and the most important information is 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 tool with no parameters and no output schema, the description is surprisingly complete: it defines what the tool does, what inputs it considers, what output shape is expected, and how it handles ambiguity. The only minor gap is the lack of examples for the 'example' field in the output plan, but that is a detail an agent can infer or clarify.

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 is empty (0 params), so schema coverage is trivially 100%. The description explains that the tool operates on user intent and auth method, and that missing information is handled by asking clarifying questions rather than through structured parameters. That adds meaning beyond the empty schema, satisfying the baseline of 4 for zero-parameter tools.

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 uses a specific verb ('Determine'), a clear resource ('Kudosity API version for each operation'), and concrete example operations (SMS, webhooks, contacts, reports). It distinguishes itself from siblings like execute-request by stating it produces a routing plan rather than executing requests, so an agent can immediately tell it apart.

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 defines when to use the tool: when the user needs to choose a Kudosity API version based on their intent and authentication method. It also instructs to ask clarifying questions if info is missing, which is a behavioral guideline. It does not explicitly name alternatives or exclusion conditions, but the purpose is clear enough that an agent can make a reasonable choice without confusion.

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