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

Annotations only declare the basic safety profile (non-readonly, non-destructive, closed-world). The description goes well beyond that: the baseThemeId copy includes order bump styling that only the dashboard can change, a copy of a built-in theme does not inherit the store's brand color unless tokens.colorPrimary is set, and omitted variable keys retain their values while null resets them. These are non-obvious side effects an agent could not infer from any structured field.

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, zero filler, front-loaded with the core action and then building outward to prerequisites and application. Every sentence carries distinct, actionable 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?

For a 3-parameter create tool with an output schema and full annotation coverage, the description supplies the creation workflow, dependency calls, and override semantics. Nothing an agent needs to invoke it correctly is missing.

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 description coverage is 100%, so name, variables and baseThemeId are already well documented in the schema. The description mostly restates that documentation (the list_theme_properties pointer appears verbatim in both places) rather than adding new parameter syntax or constraints. Baseline 3 is appropriate when the schema carries the detail.

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 ("Create a reusable theme") and immediately situates it in a workflow with named siblings (list_themes, list_theme_properties, create/update_checkout_page). An agent can distinguish this from update_theme or get_theme without opening any schema.

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?

Gives concrete when-and-how: use baseThemeId from list_themes to inherit a design, then set deltas in variables, and call list_theme_properties for supported keys. It also explains where the result gets applied. It stops short of distinguishing this tool from the sibling update_theme, so the alternative routing is incomplete.

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