List Plans

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

The readOnlyHint annotation is consistent with the description's 'list' operation. The description adds context about what information is returned (features, limits, pricing), going beyond the annotation. No contradictions or hidden side effects are disclosed.

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 two concise sentences, front-loaded with the main action, and includes a practical usage note. No unnecessary words or repetition.

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 simple read-only list operation with one optional parameter and no output schema, the description fully captures purpose, return content, and use case. The annotation and schema fill in the remaining details.

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 sole parameter billingPeriod is fully described in the schema with enum values and default. The description doesn't mention it, but with 100% schema coverage, the parameter is already well-documented. Baseline 3 applies.

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 clearly states the tool lists all ULink subscription plans with features, limits, and pricing. It uses a specific verb ('list') and resource ('ULink subscription plans'), and the additional note about comparing plans or upgrade options distinguishes it from related tools like get_subscription.

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 gives clear usage context ('useful for comparing plans or determining upgrade options'), which implies when to use it. It doesn't explicitly mention alternatives or exclusions, but the sibling list makes the distinction obvious, especially from get_subscription.

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