Set default watchlist

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

The description states the core action but adds no behavioral details beyond what the idempotentHint annotation already conveys. It doesn't mention that setting a new default unmarks the previous one or any authorization needs.

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?

A single concise sentence efficiently conveys the tool's purpose with no unnecessary words. While brief, it earns its space.

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 description does not mention return values or confirm what happens on success/failure. For a simple setter with no output schema, it lacks completeness but is minimally adequate.

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% and the input schema already describes the parameter as 'Watchlist ID to set as default'. The description does not add additional meaning beyond that.

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 'Mark a watchlist as the user's default' clearly states the action (mark/set) and the resource (a watchlist as default). It effectively distinguishes from sibling tools like create, delete, or rename watchlist.

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 provides no guidance on when to use this tool versus alternatives. It does not specify prerequisites (e.g., watchlist must exist) or side effects (e.g., overriding previous default).

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