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

Annotations already declare it is a non-destructive, idempotent write (readOnlyHint=false, destructiveHint=false, idempotentHint=true). The description adds real behavioral context by clarifying that the move replaces the existing folder assignment rather than creating a second membership, which is not implied by the annotations.

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?

One sentence, front-loaded with the core action, with the edge-case behavior appended compactly. No padding or 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?

An output schema exists and annotations cover the safety profile, so return values and mutation safety need no restating. The description covers the essential mutation semantics; only the sibling-relationship and permission context are 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 description coverage is 100%, so all three parameters are documented in the schema, including the targetFolderId=0 convention. The description merely restates that convention, adding no syntax or format detail beyond the schema; baseline 3 applies.

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 (moves) and resource (test cases) plus the effect on assignment (replacing their current folder). However, it does not differentiate from the sibling moveFolder, which an agent could confuse with this tool.

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?

It gives one actionable usage rule (targetFolderId=0 removes the cases from any folder), but offers no guidance on when to choose this over moveFolder or any prerequisites such as permissions or folder existence.

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