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

Annotations already declare destructiveHint=true and idempotentHint=false, so the safety profile is covered. The description adds real value by specifying what is destroyed ('removes its current video content') and that the variant itself is not replaced, though it does not state whether cleared content is recoverable or what state the variant is left in.

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 short sentences with the resource scope front-loaded and the disambiguation second. Every clause carries information; nothing is redundant or padded.

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 and annotations cover the destructive/idempotency profile, so return values and safety need not be restated. However, for an irreversible mutation with an optional targeting parameter, the missing guidance on the optional variantId and reversibility leaves a meaningful gap.

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%, so the description carries the full burden for two parameters, and it says almost nothing about them. It implies variantId targets a specific variant but never explains the effect of omitting the optional variantId (e.g., whether it defaults to the active variant) or what projectId must reference.

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 (clears) and resource (the specified promo-video variant's saved configuration), which is more precise than the title alone. The clause 'rather than creating a new variant' rules out the most plausible misinterpretation, though it contrasts with a behavior rather than naming sibling tools like delete_variant or generate_promo_video.

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?

No explicit when-to-use or when-not guidance and no named alternatives, even though siblings such as delete_variant, update_promo_video, and apply_promo_video_candidate clearly compete for similar intents. The only guidance is the implicit clarification that this is not a variant-creation operation.

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