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

Discloses behaviors beyond the annotations: all downstream work is deferred until payment (so no side effects beyond record creation), the call is cheap and reversible, and accepted_terms records a reseller assertion against the agent id. Annotations only mark non-read-only/non-idempotent/non-destructive, so this is valuable, non-contradictory context.

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 sentences: purpose, deferred behavior, and required term + next step. No filler; the critical operational detail is front-loaded.

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 create tool with no output schema, the description covers preconditions, side-effect timing, and the follow-up call. It doesn't specify what the response contains or how to obtain the created brand id, but that is a minor gap given the deferred workflow and sibling tooling.

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?

Adds important semantics for accepted_terms (reseller assertion recorded against agent id) and situates plan as the input consumed by checkout_create, going beyond the schema's one-liners. With 63% schema coverage, the description partially compensates for tone/niche/website, which remain unexplained in both places, so this is good but not 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?

States 'Create a brand owned by this agent' — a specific verb and resource, and the ownership qualifier distinguishes creation from brand_activate/brand_get/brand_list. Sibling tools like checkout_create are clearly later steps, so an agent can identify this as the creation entry point.

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 frames the workflow: the call is cheap/reversible because work is deferred until payment, and instructs 'Follow with checkout_create.' It does not enumerate alternative tools or exclusion conditions, so it isn't a full when-not-to-use statement, but the payment deferral and next-step pointer give clear usage context.

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