Copy file or directory

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

Annotations already declare destructiveHint=true and readOnlyHint=false, so the mutation profile is covered. The word 'recursively' adds real behavioral context (whole subtree is copied), but the description omits critical traits: whether an existing destination is overwritten, whether it fails or merges, and permission requirements.

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?

A single front-loaded sentence with no filler. It is efficient, though arguably underspecified rather than optimally concise for a destructive mutation tool.

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?

No output schema, no parameter documentation, and only an annotation-level safety signal. For a destructive recursive copy with device-targeting parameters, an agent still lacks overwrite semantics, failure behavior, and any parameter meaning.

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 0% and the description adds nothing about the four parameters. Two non-obvious fields (deviceId, deviceName) are left completely unexplained as to what they target or whether they are optional. It does not compensate for the coverage gap.

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 (copy) and resource (file or directory) plus the recursive scope, which distinguishes it from a shallow single-file copy. It does not explicitly name siblings like move_file or delete_path, but the copy verb naturally separates it from those.

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 guidance on when to use this versus move_file, fs_write_* alternatives, or device-targeted transfer tools (adb_push). Nothing about prerequisites, destination existence, or overwrite conditions is stated.

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