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

Annotations already declare readOnlyHint=true and openWorldHint=true, so the safety profile is covered. The description adds that the profile is 'public' and returns 'a page of its pin items' (implying pagination), which is useful, but it doesn't disclose pagination controls, page size, or rate limits that a fetching tool might need.

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 sentences, zero waste, with the core operation front-loaded and the sibling routing following. Nothing redundant.

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?

An output schema exists, so return values need not be explained, and the description covers purpose plus alternatives well. It is complete enough to invoke correctly, though it could note pagination behavior for the 'page of pin items' it returns.

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 `id` and points to GET /pinterest/categories for the list. The description only restates that the id is a category id, adding no format or syntax detail beyond the schema. Baseline 3 applies when the schema does the heavy lifting.

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 (Fetch), resource (one public Pinterest Ideas-category profile and a page of its pin items), and the selection key (by category `id`). It clearly distinguishes itself from siblings like pinterest_board, pinterest_user_pins, and pinterest_search.

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 routes the agent: pinterest_categories to discover categories, pinterest_board for a board feed, pinterest_user_pins for a user's pins, pinterest_search/pinterest_pin for discovery or detail. The when-to-use and alternatives are spelled out with no inference needed.

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