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

Annotations already declare readOnlyHint=true, destructiveHint=false and closed-world, so safety is covered. With no output schema, the description usefully discloses the return payload's contents (texts with hints and max lengths, palette, fonts, photos), which is the key behavioral detail an agent needs. It does not describe the response structure or size, keeping it short of a 5.

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?

Two sentences, front-loaded with what is returned, then the follow-up action. No filler, and every sentence carries information an agent can act on.

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?

With no output schema and only two parameters, the description covers what the brief contains and what to do with it, which is close to sufficient. It could add a note on whether the returned texts are templates to be rewritten versus fixed content, which would fully close the loop.

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%: design_id's provenance from explore_designs and language's effect on word limits are both documented in the schema. The description adds no format or syntax detail beyond that, so the baseline 3 applies.

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 (returns the design brief) and enumerates its contents: texts with hints and max lengths, color palette, fonts, photos. It also names the downstream consumer, generate_site, which separates it from siblings before the agent opens 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 clear workflow context — write the returned texts for the user's business, then pass the values to generate_site — and the schema ties design_id to explore_designs. However, it never states when not to use this tool or what an alternative would be.

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