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

With annotations already declaring readOnlyHint=false, idempotentHint=false and destructiveHint=false, the description adds real value: it discloses that all supported formats are produced, that cached layouts are reused without a new generation, and that an editor link is returned. It omits whether repeated calls create duplicate variants or what caching invalidation looks like, which matters for a non-idempotent mutation.

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 the action and the source of inputs, then the side effects. Tight overall, though 'includes all supported formats' is slightly vague and could be more precise about what set of outputs that means.

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?

An output schema exists, so return values need little explanation, and the caching behavior is disclosed. However, for a non-idempotent creation tool with six parameters, the description leaves open whether it overwrites an existing variant, what happens on repeat calls, and how catalogKey/templateId are obtained.

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 67% and the schema already documents projectId/generationId alias, paletteMode and primaryFormat. The description adds nothing about catalogKey or templateId, the two undocumented required parameters, so an agent gets no help on where those values come from beyond 'prepared catalog and selected style'.

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 a new social-graphics variant from a catalog key and selected style, which clearly separates it from siblings like render_graphics or prepare_social_graphics_styles. It doesn't name the sibling it depends on explicitly, so the differentiation is implied rather than stated.

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?

'from a prepared catalog and selected style' hints that prepare_social_graphics_styles must run first, but the prerequisite is never named and there is no when-not guidance (e.g. vs render_graphics or save_graphics). The usage context is inferable but not explicit.

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