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

Annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false. The description adds value by specifying exactly what it does not do (create checkout, invoice, charge, entitlement, payment obligation) and emphasizing the human-in-the-loop requirement. This goes beyond the annotations and clarifies the tool's side-effect-free nature.

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 exactly two sentences: the first states the core purpose, the second clarifies non-obligation and human involvement. It is front-loaded and every word earns its place, with no filler or 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 handoff tool, the description gives enough to understand its role, but it does not explain what the returned URL looks like, how the agent should present it, or what happens if the offer_key is invalid. With no output schema, the description should clarify the return value and usage flow; it leaves these gaps. However, the core purpose and safety are covered.

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?

Schema description coverage is 0%, and the description provides no explanation of any parameter. While parameter names like offer_key (with an enum) are somewhat self-explanatory, the description does not compensate for the lack of schema descriptions. The agent is left to infer the meaning and format of source, event_id, and event_title without guidance.

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 a specific verb ('Prepare') and resource ('review URL for a selected EventWave promotion package'), and explicitly distinguishes itself from checkout by stating it does not create checkout, invoice, charge, entitlement, or payment obligation. This differentiates it from the sibling prepare_event_promotion_checkout and makes the purpose unambiguous.

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 conveys that this tool is a precursor to checkout and requires human action, but it does not explicitly name the alternative tool (prepare_event_promotion_checkout) or state conditions for when to use this vs. that. The context is clear enough for an agent to infer usage, but an explicit exclusion would be stronger.

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