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

The description usefully explains the surprising annotation combination: readOnlyHint=false and non-idempotent are accounted for by 'uses one read and saves the result in the user's Puley history', which the agent could not infer from the annotations alone. It also discloses the limit ceiling of 25. It says nothing about cost, rate limits, or what happens on subsequent identical calls despite idempotentHint=false.

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 core statement and free of filler; the returned-field enumeration earns its space because there is no output schema. The sentence is long and dense, but nothing is 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?

With no output schema, describing the returned fields and the linked-sites summary is exactly the needed compensation, and the history side effect is disclosed. Gaps remain around query formatting and whether a follow-up call (e.g. more_results) is needed to go past 25.

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 description coverage is 0%, so the description must carry both parameters. It adds real meaning for limit ('up to 25', matching the schema default but revealing the cap) and implies query is a topic/search string. It gives no query syntax guidance (keywords vs phrases, language, locale), leaving the main required parameter underspecified.

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 resource ('Pinterest's top pins') plus scope ('for a search, as Pinterest ranks them') and enumerates what each result carries. It is readily distinguishable from sibling search tools such as find_videos, search_posts, and google_results.

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 frames when this applies ('good for ideas and inspiration... and for seeing which sites and creators rank on Pinterest for a topic'), which steers the agent well. It does not name an alternative tool or state when not to use it, so it falls short of the top band.

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