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

Annotations already establish this as a non-destructive, closed-world mutation, so the bar is lower. The description adds genuinely non-obvious behavior: variants travel with the parent project, and a project lacking a brand kit inherits the folder's kit. It omits error behavior and the 200-item batch ceiling, but the inheritance rule is real value beyond structured fields.

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 compact sentences with the core action front-loaded and the side effect following. The parenthetical '(by brand, campaign, anything)' is slightly loose but serves as a usage cue rather than filler.

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?

For a two-parameter, no-output-schema tool with annotations covering the safety profile, the description covers purpose, cascade behavior, and brand-kit inheritance. The folder-creation and null semantics live in the schema, so nothing an agent needs to call this correctly 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 only 50%: 'folder' is well documented in the schema including the null case, while 'projectIds' has no schema description at all. The description adds nothing about projectIds (identity format, batching, the 200 cap), so it does not compensate for the gap but the array name remains largely self-explanatory.

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?

The description states a specific verb and resource ('Move projects into a folder') plus a secondary effect ('their variants with them'), which cleanly separates it from siblings like move_clip, move_media, or update_folder. It stops short of naming a sibling alternative explicitly, so it is clear but not fully differentiated.

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?

Usage is implied through the rationale 'to keep the user's work split (by brand, campaign, anything)', which tells the agent the organizing intent. There is no explicit when-not guidance, no mention of prerequisites such as listing projects or folders first, and no pointer to list_folders or list_projects for discovery.

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