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

With no annotations, the description carries the full burden and does well: it discloses that the return is a hosted Stripe checkout URL, that card entry happens on Stripe and never within agent scope (a meaningful security boundary), and that the license lands in the user's library post-payment. It does not address repeat/idempotent calls or auth prerequisites, leaving a small gap.

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?

Three compact sentences with no filler; the core action and its payload are front-loaded, followed by the payment-safety note and the post-purchase next step.

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?

Given no output schema and no annotations, the description supplies the return value (checkout URL), the security boundary for payment, and the follow-up tool. That is sufficient for a single-parameter purchase-initiation tool, with only auth/idempotency behavior left unaddressed.

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?

Only one parameter with 100% schema coverage, so the baseline is 3. The description adds no syntax or format detail beyond what the schema already states, including the example slugs that already appear in the property description.

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 and resource ('Begin purchase of a PAID Artemis GTM agent or bundle') and immediately scopes it to paid items, distinguishing it from the sibling claim_free_agent. It also names the deliverable (a hosted Stripe checkout URL), so an agent knows exactly what the call produces.

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 makes clear this is for paid agents/bundles and routes the agent to the follow-up step (get_install_command after payment). It never explicitly says to use claim_free_agent for free items, but the capitalized 'PAID' scoping carries that implication.

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