Register the brands you publish under

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

With no annotations, the description carries the full burden. It usefully discloses that data is 'stored on this machine only', but for a mutating tool it does not say whether set overwrites an existing profile, what remove destroys, or what list returns. The local-persistence note is real added value, but mutation semantics are missing.

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 dense sentences, front-loaded with the purpose and rationale ('so the right logo is never guessed'), followed by workflow links and the action set. Little waste, though the rationale clause could be trimmed without loss.

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 an 11-parameter tool with no annotations and no output schema, the description leaves key behavior unexplained: what a list result contains, whether set is an upsert, and what remove clears. The workflow and persistence notes help, but an agent still has to infer mutation semantics.

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 only 36%, so the description must compensate. It does explain publisher ('a person posting as themselves, or a company'), the dark-vs-light logo distinction, and that palette and fonts are optional, but leaves name, colors format, used_for, body_font/heading_font, and google_fonts_url to the schema. Partial compensation only.

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 states the resource (a per-brand profile holding publisher type, dark/light logo files, optional palette and fonts) and the supported operations (list, set, remove). It also names the siblings it feeds (design_brief, compose), so an agent can place it in the workflow. The verb is soft ('keeps a profile') rather than an explicit 'register/read brand profiles', which keeps it just short of a 5.

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 says design_brief takes brand_id and fills these in, and compose places the logo, which implies this tool should be populated before those run. However, there is no explicit instruction on when to call it (before composing? on first run?) or how to choose between list, set, and remove.

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