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

The description is consistent with readOnlyHint=true and adds a substantive domain rule the annotations cannot express: 'People never pay' is a pricing-policy fact, not a mutability fact. It does not describe response shape, but for a static reference lookup with a read-only annotation, that omission is minor.

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?

Two short sentences, the core subject (who pays, by connection direction) is front-loaded, and the qualifier follows. 'People never pay' is terse to the point of being slightly cryptic out of context, but nothing is wasted.

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 informational tool with no output schema, the description covers the substance of what an agent gets back: which direction of connection incurs payment, what each plan contains, and the global rule that individuals never pay. Nothing further is required to decide whether to call it.

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 no parameters, so there is nothing for the description to disambiguate. Baseline of 4 applies since the schema cannot be a source of misuse here.

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?

States a specific resource (pricing/plans) and a specific scope (connection direction, plan contents) with the verb 'explain'. It is distinguishable from siblings like ventru_usage and ventru_trust_profile, though it never names them explicitly.

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 rather than stated: an agent can infer this is the reference lookup for pricing questions. There are no explicit triggers, no exclusions, and no pointer to ventru_usage for actual consumption/billing volume, which is the nearest sibling and a plausible source of confusion.

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