fs_move

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

Annotations already convey destructiveHint and readOnlyHint=false, so the description does not need to restate mutation. It adds valuable context beyond annotations by warning that the VM remains locked by the session and must be unlocked via vm_unlock. This is a meaningful behavioral side effect for an agent to account for after invocation.

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?

The description is two short sentences with no wasted words. The primary operation is front-loaded, and the lock-unlock warning is a necessary secondary detail. Every sentence earns its place.

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 the core operation and a key side effect, but it is incomplete for a destructive tool with no output schema and low parameter documentation. It does not clarify what happens when overwrite is true or whether the source/destination paths are expected to be guest-absolute paths. The lock warning helps, but the overall picture requires inference.

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 only 25%, with only vm_name described. The description adds little parameter-level meaning: it implies source and destination are guest paths but does not explain path format, overwrite behavior, or the meaning of the overwrite flag. With low schema coverage, the description needed to compensate and did not.

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 clearly states the specific action ('Move or rename') and resource ('a guest file or directory'), distinguishing it from sibling tools like fs_delete and fs_mkdir. It is specific enough that an agent can select it for move/rename operations without opening the schema.

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?

The description implies usage for moving or renaming guest files and directories, and adds the important lock-lifecycle instruction to call vm_unlock. However, it does not explicitly mention when not to use it, such as when copying or when operating on host files, nor does it name alternatives.

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