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

Goes well beyond the annotations: nothing is charged, no order exists until payment, each print is re-priced server-side and request prices are ignored, and both returned links have distinct lifetimes (order_link 7 days, checkout_url 2 hours). This tells the agent exactly what mutation occurs and what to hand back to the person, which readOnlyHint=false/openWorldHint=true alone does not.

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-loads the core action and the no-charge guarantee, then handles parameters, then return values. It is dense and slightly long with one run-on enumeration of excluded product types, but every sentence carries operative information.

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?

With no output schema, the description fully carries the return contract (order_link vs checkout_url, their lifetimes, and which to give the person). Combined with the pricing and shipping caveats, an agent has everything needed to call this correctly and relay results.

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 coverage is 100%, so baseline is 3, but the description adds real meaning: prints must be the checkout_item exactly as quote_custom_print returned it (prices ignored from the request), and the destination ZIP/postal code is required because shipping is priced to it. It does not explain agent, email, or the per-item finish/quality/infill fields, which remain schema-only.

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 (creates a Stripe Checkout link for custom prints) plus the exact precursor (quote_custom_print output). It also draws the boundary against the catalog/figures/keychains path, so the agent can distinguish it from siblings like search_products without inspecting schemas.

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?

Explicitly says when to use it (custom prints quoted with quote_custom_print, person pays in browser) and when not to (catalog products, figures, keychains, lithophanes, cake toppers, cookie cutters get their own pages from search_products or print_price_examples). The prerequisite chain to quote_custom_print is stated outright.

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