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

Annotations already declare readOnlyHint=true and destructiveHint=false, but the description goes further by explicitly stating it 'creates no checkout, invoice, charge, or payment obligation.' This adds concrete behavioral context beyond the structured hints, reassuring the agent about side-effect-free invocation.

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 tightly packed sentences: the first states the action and scope, the second reinforces safe read-only behavior. No filler, no repetition of schema or annotation fields, and the key detail 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 parameterless list operation with strong annotations and a simple output expectation, the description covers everything an agent needs: what is listed, that it is current, and that no financial obligation is created. No output schema exists, but the task is simple enough that no additional return–format details are required.

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 has zero parameters)Skip the input schema is empty and schema coverage is trivially 100%. With no params, there is nothing the description needs to explain; the baseline of 4 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 opens with the verb 'List' and identifies the exact resource: 'current EventWave paid promotion packages'. Adding 'evidence/payment boundaries' clarifies the scope and distinguishes this from siblings like get_eventwave_promotion_status or prepare_event_promotion_checkout.

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: it lists current paid promotion offers, and the read-only disclaimer suggests using this when no side effects are desired. However, the description does not explicitly name alternatives or state when not to use this tool, so an agent must infer routing from sibling names.

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