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

Annotations already declare readOnlyHint=true and destructiveHint=false; the description reinforces this with an explicit negative list of side effects (no image generation, no project save, no render, no publish). That is genuinely useful disambiguation beyond the annotations, though it says nothing about cost, latency, or result shape.

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 short sentences, front-loaded with purpose, then the templateId rule, then the scope boundaries. Every sentence carries distinct information with no repetition of the title.

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?

The description covers purpose, the key templateId branch, and non-goals, and sketchily characterizes the output ('three-beat visual proposal and recommended template'). But for a 7-parameter tool with a nested object and no output schema, the undocumented parameters leave a meaningful gap before an agent can call it correctly.

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 0% across 7 parameters including a nested acceptedDesign object, yet the description only explains templateId. It gives no meaning for brief, title, body, cta, aspect, or the required sub-fields of acceptedDesign (style, durationSeconds, audio, illustration, exclusions).

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 concrete verb and resource: 'Turn an ordinary video request into a three-beat visual proposal and recommended template.' The closing negations ('does not generate images, save a project, render, or publish') carve out scope against render/publish siblings, though no sibling is named explicitly.

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 explicit conditional guidance for templateId: pass it to preserve an accepted template when changing only the aspect, omit it for a new direction. It also signals via exclusions that rendering/publishing belong to other tools, but never names the alternative tool to call.

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