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

Annotations already declare the mutation/safety profile (readOnlyHint=false, destructiveHint=false, idempotentHint=false), so the description's job is to add context — which it does with the credit-cost fact and the cache-lag caveat for list_boards. It stops short of stating permissions/scope requirements or failure modes for the create call itself.

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?

Content is front-loaded on the trigger and return value, and every sentence carries operational information (credits, cache behavior, account disambiguation). It is on the long side for one tool but has no filler.

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?

With an output schema present the description needn't detail the return shape, yet it still names boardId and its downstream consumers (create_post, schedule_post). Combined with the annotated safety profile and full schema coverage, an agent has everything needed to call it correctly.

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 schema already documents name, privacy, accountId, and description. The description only reinforces the accountId source, adding no new semantics for privacy or the description field beyond what the schema states.

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?

Opens with a precise verb+resource+scope ('creates a board on their account') and makes the return value explicit (numeric boardId). It is clearly distinguishable from create_board_section, create_board_list, and list_boards by naming what it does and where its output goes.

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?

Gives an explicit trigger ('when the user wants a new Pinterest board'), the prerequisite path (accountId from list_accounts), and an explicit disambiguation/instruction to ask the user when multiple accounts exist rather than choosing. It also routes the agent away from the list_boards alternative for retrieving the new board.

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