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

Annotations already declare readOnlyHint, idempotentHint, non-destructive and closed-world, and the description reinforces this with 'Creates nothing and spends nothing' — genuinely useful reassurance about side effects and cost. It stops short of noting whether links expire or can be shared, but the core behavioral contract is well covered.

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 short sentences, front-loaded with the return value and followed by the handoff behavior and the no-side-effects guarantee. No filler.

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 one-parameter, no-output-schema tool, the definition covers what is returned, who completes the action, and that nothing is created or billed. Only minor details (link lifetime, reusability) are absent, which is a small gap.

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% and the single parameter already documents the 1800-character limit. The description only adds that the prompt becomes pre-filled content in the builder, which is helpful framing but no new syntax or constraint information.

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: returns a link that opens the GYSM builder with the prompt pre-filled. The clause 'The user signs in and presses build themselves' further pins down what the link does, separating it from tools like start_checkout or plan_app that act on the user's behalf.

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?

Implies the when: use this when you want to hand the build off to the user in the UI rather than doing anything programmatically. There is no explicit 'use X instead' routing, but the sign-in-and-press-build condition is a clear usage context.

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