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

With no annotations, the description carries the burden and does disclose one key behavior—'Does not complete payment'—preventing misuse as a payment tool. However, it does not state whether opening a checkout creates a session, reserves inventory, or requires special permissions, so operational side effects remain opaque.

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 a single concise sentence with the main action front-loaded and the critical non-payment clarification appended. No filler 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 tool with no annotations and no output schema, the description is too sparse: it omits the meaning of offer_index, the shape of the returned URL, and any prerequisites or side effects. An agent calling this tool correctly would need more context than provided.

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%, so the description must explain the parameters. It aligns 'quote' with quote_id but says nothing about offer_index, its optionality, or how it modifies the returned URL. An agent cannot reliably decide whether or how to set offer_index.

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?

Description uses a specific verb ('Return') and resource ('merchant product/checkout URL') tied to a quote, and explicitly states what it does not do ('Does not complete payment'), making its purpose unambiguous and distinct from siblings such as get_quote or post_offer.

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 phrase 'for a quote' implies this tool is used when a quote exists and a checkout URL is needed, but it names no sibling alternatives or when-not-to-use conditions, leaving the agent to infer the decision boundary among the eight sibling tools.

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