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

Annotations already declare readOnly/idempotent/openWorld/non-destructive, but the description adds meaningful context: it is a 'handoff' that the customer reviews as a whole basket and then authorizes payment separately, so no charge occurs here. The 'fresh' wording and mc-bundle-one note add operational nuance beyond the annotations.

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?

Front-loaded with the core action and then the invocation contract; every sentence carries weight. 'Existing mc-bundle-one is supported' is slightly cryptic out of context but still earns its place as a compatibility note.

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?

No output schema exists, but the description conveys the downstream flow (customer reviews basket, authorizes payment), so the agent understands what the handoff produces. For a 2-parameter tool this is nearly complete, lacking only an explicit note on sibling alternatives.

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 compensate. It explains that productIds holds one or two exact catalog IDs, offerId is a single offer, and the two are mutually exclusive ('never both') — a constraint not expressible in the schema itself.

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 verb (prepare) plus resource (purchase handoff) and scopes it to published courses/books or an exact course+book pair. This clearly distinguishes it from siblings like list_products, list_offers, and recommend_offer, which don't construct a basket.

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?

Gives concrete invocation guidance: pass productIds (one or two exact catalog IDs) OR a single offerId, and 'never both'. It also notes mc-bundle-one support. It stops short of explicitly contrasting when to prefer this over recommend_offer or list_offers, so guidance is clear but not exhaustive.

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