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

Annotations already declare destructiveHint/readOnlyHint/idempotentHint, but the description adds material behavior: the copy-then-delete implementation, the failure mode when the destination key exists, and the irreversibility of both overwrite and source deletion. That is real value beyond the structured hints.

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?

Three compact sentences, each carrying a distinct fact (mechanism, precondition, failure/irreversibility), with the destructive semantics front-loaded. No filler or restatement of the name.

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 6-parameter mutation with no output schema, the description covers mechanism, preconditions, failure behavior and irreversibility. It stops short of noting cross-bucket/cross-connection scope or any permission requirements, which is the only remaining gap.

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 100%, so the baseline is 3, but the description adds meaning the schema lacks: overwrite gates a failure rather than merely 'replacing', and the overwrite/source-delete actions are irreversible. The destination-must-differ constraint also ties two otherwise-plain parameters together.

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 (object), and goes further by explaining the mechanism: copy to destination then permanently delete source. That mechanism implicitly separates it from copy_object (non-destructive) and delete_object (single-resource removal) in the sibling list.

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 gives preconditions (destination must differ from source, fails on existing key unless overwrite) but never states when to choose this tool over copy_object plus delete_object. Usage is implied by the copied-then-deleted semantics rather than explicitly routed.

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