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

Annotations already declare readOnlyHint and openWorldHint, so the safety profile is covered. The description adds two genuinely useful facts not in the annotations: results are public-only, and the call "Costs 1 credit." It does not say how results are paged or bounded in count, leaving the cursor flow implicit.

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?

Three short sentences, front-loaded with the action, then scope, then cost. Nothing is redundant and no sentence could be removed without losing information.

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 read-only search tool with annotations and a documented required parameter, the description supplies the essentials: what it searches, that results are public, the output framing ("unified posts"), and the credit cost. The only real gap is pagination expectation, which the cursor parameter partly implies.

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 67%, with query and cursor well documented in the schema itself. The description adds no parameter meaning beyond the schema — notably cache_max_age is undocumented in both places — so it does not compensate for the remaining gap; baseline 3 applies.

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?

The description states a specific verb and resource ("Search pins") and narrows scope to "Public Pinterest search results for a query," which separates it from the sibling lookup tools pinterest_pin, pinterest_board and pinterest_userBoards. It stops short of naming those siblings explicitly, so the agent must infer the boundary from the word "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?

Usage is implied by "Search pins ... for a query" — the agent can infer it is the entry point when it has keywords rather than a known pin or board ID. There is no explicit when-to-use/when-not guidance, no mention of when to prefer pinterest_pin for a known ID, and no prerequisites stated.

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