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

Annotations only supply destructiveHint=true, so the description carries the real burden — and it does: it discloses the split-item-with-same-sid outcome of partial moves, the merge-at-destination rule, that the returned id is the destination's, and the undo path. That is exactly the consequence information an agent needs before a destructive write.

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?

Dense and front-loaded: purpose and scope first, then the three behavioral outcomes, then the undo hint and the WRITE flag plus endpoint. Every sentence carries distinct information with no repetition.

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 destructive 4-parameter write with no output schema, the description supplies the mutation outcomes, the semantics of the returned id, and the recovery path. Nothing material is missing for correct invocation.

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 genuine meaning beyond the schema: 'some or all of an item's quantity' clarifies how the quantity parameter interacts with the partial/full move behavior, and the merge rule relates the returned id to the destination. It stops short of documenting leave_zero_quantity explicitly.

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 and resource — moving an item's quantity to another folder — and explicitly scopes it to items only, pointing folder relocation at sortly_update_item instead. An agent can distinguish this from siblings like sortly_update_item without opening either 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?

Explains the operational contexts well: partial move splits a new item, full move relocates, matching destination merges, and undo is done by moving back. It names the sibling for the folder case, but does not state when to prefer this over recreating/updating an item, so exclusions beyond folders are implicit.

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