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

With no annotations to lean on, the description carries the full load and does so well: it declares two negative side effects (it does not accept terms on the owner's behalf and does not email the Terms), the refusal behavior when the precondition fails, and the critical one-time disclosure that the reply's agent key is shown only once. These are exactly the traits an agent cannot learn from the schema.

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?

Four short sentences, front-loaded with the create action and its precondition, then the negation and the return-value caveat. Slight redundancy in re-listing the required fields that the schema already marks required, but nothing is wasted overall.

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 7-parameter creation tool with an output schema (so return shape need not be explained), the definition covers preconditions, refusal, side effects and the one-time secret. The remaining gap is routing: it never contrasts itself with shops_create or states any auth/permission requirement for the caller.

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 57%, and the description compensates by spelling out the required set (accept_terms true, shop name, jurisdiction, owner name and email) and by reinforcing what accept_terms=true actually attests. The two undocumented-in-description parameters, agent_name and accept_terms_version, are covered by their own schema descriptions, so the combined picture is close to complete.

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?

The description gives a specific verb and resource ("Create a shop") and adds a decisive qualifier: the owner must already have accepted the Terms and Privacy on the sign-in page. That condition separates it from a generic shop-creation path, but it never names the obvious sibling shops_create, so an agent must infer the distinction rather than being told.

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?

It states the precondition clearly (owner already accepted on the sign-in page) and the negative case (call is refused and points to the sign-in page), which is strong when-to-use guidance. What is missing is an explicit alternative pointer, e.g. use shops_create when the owner is not signing up through this flow.

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