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

Annotations already flag destructiveHint=true and idempotentHint=true, and the description adds the specifics those hints cannot carry: the call is a full replacement, any board omitted is removed from the list, and removing a board does not alter the board itself or its Pins on Pinterest. It also confirms retry safety and that the operation is free, which are not in the annotations.

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?

Front-loaded with the trigger condition, then the replacement contract, then the compensating procedures and caveats; nearly every clause carries decision-relevant information. Minor redundancy with the schema's boards description (the intervalBoards note) and the 'free' remark is incidental, but neither derails the read.

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?

A destructive, idempotent full-replacement tool with an output schema and fully documented parameters — the description covers everything an agent needs before calling: trigger, replacement semantics, what survives, retry behavior, and the account-disambiguation protocol. No material gap remains.

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% and the schema already documents publishing order, uniqueness, and the 20-board interval constraint, so most parameter meaning is pre-supplied. The description still adds one genuinely new semantic: the boards array behaves as a replace-set, so omission means removal — the decisive behavior an agent needs when filling that parameter.

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+resource (update a board list) and enumerates the three concrete sub-operations it supports: rename, add/remove boards, reorder publishing. It also distinguishes itself from the read-side sibling by pointing at list_board_lists as the source of current boards, so an agent can tell it apart from create_board_list/delete_board_list without opening any 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?

Explicitly says when to use it ('when the user wants to rename... add or remove boards... or change the order'), then gives the exact procedure for the two tricky cases: rename-only must resend current boards unchanged, reorder must resend the same boards in a new order. It also adds a genuine precondition: if list_accounts returns more than one account and the user didn't specify, ask rather than choosing.

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