BooksPinLessonToClass

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

The annotation readOnlyHint=false indicates mutation, and the description's 'Pin' verb aligns with that, so there is no contradiction. However, the description adds no behavioral context beyond the annotations: it does not mention side effects, whether pinning is idempotent, what happens on repeated pinning, or any permission requirements.

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 a single, front-loaded sentence with no filler or redundant information. Every word contributes to identifying the operation, making it highly concise and easy to parse.

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 simple two-parameter mutation tool, the description is too sparse to fully support correct invocation. It omits what 'pin' means operationally, what the response is, and how the 'book' element is resolved given the provided parameters. The absence of an output schema increases the need for more contextual disclosure, which is lacking.

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?

The schema has 0% description coverage and no parameter descriptions, so the description must compensate. It mentions 'lesson' and 'class', which loosely map to bodyLessonId and bodyClassId, but it does not explain the relationship between the parameters, whether both are required, or how the book is identified despite being mentioned.

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 a specific action ('Pin'), a resource ('a lesson'), and a target ('a class'), which distinguishes it from siblings like BooksGetBook or GroupClassesGetList. However, the phrase 'from a book' is ambiguous because no book identifier appears in the parameters, slightly reducing clarity.

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?

The description gives no guidance on when to use this tool versus alternatives, nor when not to use it. No sibling comparison or prerequisite context is provided, so an agent is left to infer the appropriate scenario.

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