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

Annotations declare destructiveHint=true and readOnlyHint=false, so danger is already signalled. The description adds genuinely useful beyond-annotation detail: it refuses to overwrite and performs no move when the destination exists, which is exactly the failure-mode an agent needs to anticipate.

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 tight sentences with zero filler; the core action comes first and the destructive constraint follows. 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?

For a two-required-parameter mutation tool with safety annotations and no output schema, the description covers the critical behavior (no overwrite, no partial move). The remaining gap is path/format semantics for source and destination.

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 33%: device is documented in the schema but source and destination have no descriptions. The description references 'destination already exists' but never clarifies what source/destination accept (path format, relative vs absolute), so 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 (move/rename) and resource (file or folder), which is immediately distinguishable from siblings like write_file, edit_block, or create_directory. It does not explicitly name an alternative tool, so it stops short of the top tier.

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 by the verb, and the overwrite clause gives a concrete behavioral precondition, but there is no explicit when-to-use guidance and no mention of sibling alternatives (e.g. write_file for copying content).

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