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

Annotations already declare readOnlyHint=true and openWorldHint=false, so the safety profile is covered. The description adds valuable context beyond that — the exact return fields and the downstream apply workflow — but says nothing about pagination, result limits, or rate behavior.

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?

Front-loads purpose, then the apply workflow, then optional filters. Slightly long but each sentence (purpose, returns, application mapping, filters) earns its place with no redundancy.

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, the description compensates by enumerating return fields and fully explaining the downstream application path. Nothing an agent needs to browse and then apply an effect is missing.

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 100%, so both parameters (query, category) are already documented in the schema. The description restates the filtering behavior without adding syntax or format detail beyond what the schema provides, so the baseline 3 is appropriate.

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 (Browse) and resource (Popcraft's curated video effects), enumerates what the effects contain (reference video + recipe prompt) and what the tool returns (ids, names, categories, previews, recipe). Clearly distinguishable from siblings like popcraft_show_elements or popcraft_models_explore.

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?

Explicitly routes the agent: to apply an effect it names the sibling popcraft_generate_video and spells out the exact model/medias/prompt mapping. It also states the optional filtering conditions (category or query substring), leaving little to inference.

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