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

Annotations already declare readOnlyHint, idempotentHint, and closed-world, so safety is covered. The description adds genuinely non-annotated behavioral context: it works without authentication, making it a public/safe discovery call. It doesn't discuss rate limits, but that's minor here.

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?

A single sentence, front-loaded with the most important cue ('Public first step'), with every clause adding distinct information. No waste, no redundancy.

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 zero-parameter discovery tool with an output schema present, the return values need not be described. The description covers purpose, auth posture, and entry-point role, which is nearly everything an agent needs; only richer routing detail is missing.

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 takes zero parameters, so there are no parameter semantics to document; the baseline for a no-param tool is 4. Nothing in the description creates ambiguity about inputs.

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 names a specific verb (read/get) and concrete resources (capabilities, public prices, input guidance, next actions), so the agent knows exactly what it retrieves. It also frames itself as the 'public first step,' distinguishing it from the auth-gated siblings, though it doesn't name a specific alternative tool.

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?

'Public first step' and 'without authentication' clearly signal when to reach for this tool — as an unauthenticated entry point — which is strong contextual guidance. It stops short of explicit when-not conditions or naming a sibling alternative, so it's not a full 5.

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