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

Annotations already declare readOnly=false, destructive=false, openWorld=false, so the safety profile is covered. The description adds genuinely non-derivable behavior: the created brand is empty, and a plan limit produces an upgrade link rather than an error — that detail materially changes how an agent should interpret a response. It stops short of stating what identifier or payload is returned or whether duplicate names are permitted.

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 tight sentences, front-loaded with the usage condition, then scope, then the required field, then the exclusion and the edge case. No filler and nothing buried.

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 three-parameter create tool with no output schema, the description covers trigger, scope, required input, the sibling it must not be confused with, and the failure mode a caller will actually encounter. Nothing an agent needs in order to call 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%, and the schema's own text ('as the user says it', 'if the user has said') already conveys the important semantics. The description only restates that `name` is required and says nothing about about/audience, so it fails to beat the baseline set by a fully documented schema.

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+resource ('Creates an empty brand under their account') and immediately scopes what the result is — an empty shell to be filled in later. It explicitly separates itself from update_brand, so an agent can route without reading either 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 an explicit trigger ('only when the user asks to create, add or set up a new brand, business, client or project') and an explicit exclusion with the correct alternative ('Do not use it to rename or change a brand that already exists; use update_brand'). Both when and when-not are covered.

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