set_default_library

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

With no annotations provided, the description bears the full burden of disclosing side effects. 'Set' clearly signals mutation, but the description does not say whether the default persists across sessions, affects all later operations, requires authorization, or has a confirmation/return value. This is a meaningful gap for a state-changing tool.

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 redundancy. It communicates the essential action immediately and every word earns its place.

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 one-parameter setter with a fully documented enum, this description is minimally viable: an agent knows what to call and with what value. However, with no annotations or output schema, the lack of persistence/side-effect information and any guidance on how the returned state is reported leaves the context incomplete for confident use.

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 input schema fully documents the single parameter, including the enum values 'group' and 'personal' and a description for 'library'. The tool description adds no parameter detail, but with 100% schema coverage the baseline of 3 is appropriate; nothing extra is needed.

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 names a specific action ('Set') and resource ('default library'), making the tool's purpose clear. It is distinct from the search/list sibling tools, though it does not explicitly contrast itself with them. It is slightly generic in not defining which 'operations' are affected, but the core function is unambiguous.

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 implies this tool is used when the user wants to establish a persistent default, contrasting implicitly with siblings like search_personal_library or search_group_library. However, it gives no explicit when-to-use instructions, prerequisites, or alternatives, leaving the agent to infer placement.

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