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

Annotations already declare readOnly, idempotent, and openWorld hints. The description adds valuable context beyond that: boards are public-only, the trim parameter collapses response size with a specific field list, and pagination uses a cursor. It does not cover error handling or rate limits, but with annotations handling the safety profile, this is sufficient.

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?

The description is relatively long but well-structured: main purpose first, then field list, then trim behavior, then handle format, then routing to alternatives. The field list is somewhat redundant given the output schema exists, but the overall organization keeps it usable without being bloated.

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?

The tool has a simple two-parameter schema and an output schema, so the description doesn't need to explain return values. However, it mentions a cursor for pagination without explaining how to actually use it (there is no cursor parameter in the input schema), leaving a gap in how to fetch subsequent pages. It also omits any behavior for invalid usernames, though annotations cover safety.

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 baseline is 3. The description adds meaningful detail: it clarifies the handle format with an example and explains the trim parameter's effect (size reduction and which fields are retained). This goes beyond the schema's brief descriptions.

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 clearly states the tool lists a user's public boards by username, with a specific verb and resource. It also differentiates from siblings by explaining when to use get_pinterest_board and get_pinterest_search instead, so an agent can select it without opening other schemas.

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?

It explicitly says to feed each board's url to get_pinterest_board to read pins and to use get_pinterest_search for cross-Pinterest searches. It also clarifies that the handle is a bare username (agkelsey, not a full URL), giving concrete input guidance. This leaves little room for misuse.

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