x_list_update

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

Beyond the annotations, it discloses partial-update behavior ('only the provided fields change'), ownership/auth scope ('authenticated user's own'), and the policy caveat that the tool is disabled under read-only policy. This adds meaningful context without contradicting the annotations.

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?

One compact sentence front-loads the action and resource, then states the key call constraint and policy note. There is no redundant or filler content.

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 output schema covers return shape, the input schema covers field constraints, and the description covers ownership, partial-update behavior, and policy disabling. An agent has everything needed to decide whether and how to call this tool correctly.

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 already documents all four parameters with 100% coverage, so the baseline is 3. The description adds a semantic constraint not fully encoded in the schema: at least one of name/description/private must be supplied and omitted fields remain unchanged.

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 verb ('update'), a clear resource ('the authenticated user's own list metadata'), and enumerates the mutable fields. The 'own list metadata' phrasing differentiates it from list creation, deletion, following, pinning, and membership operations.

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?

Clearly establishes that this tool modifies an existing list's metadata and that at least one field must be provided. It gives solid context for when to use it, though it does not explicitly name alternatives such as x_list_create or x_list_delete.

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