longpress

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

With no annotations provided, the description carries the behavioral burden. It discloses the 210s timeout, the existence of a caller-supplied budget to extend it, and the default hold duration behavior around durationMs—all beyond what the schema states. It does not detail failure modes or side effects, but the output schema helps cover response shape.

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?

Three short sentences, front-loaded with the action and resource, then purpose, optional override, and timeout. Every sentence earns its place with no redundancy.

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 tool with 23 parameters and no annotations, the description covers the most critical aspects: what the tool does, how to specify the target, the duration override, and the timeout behavior. The extensive schema and output schema document the remaining parameters and return shape, making this adequately complete without being verbose.

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 genuine meaning by clarifying that durationMs overrides an unsuitable default, and by summarizing the three target variants (ref, selector, coordinates) in plain language. This goes beyond the schema's raw 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 opens with the specific verb 'Hold' and identifies the resource (a UI target) along with the three accepted target forms: snapshot ref, selector, and coordinates. It also states the intended outcome ('open a context menu or perform another hold gesture'), which clearly separates it from sibling tools like click or press.

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 clear usage context by stating the purpose (context menu or hold gesture) and offers a conditional parameter guidance ('Set durationMs when the default hold duration is unsuitable'). It does not explicitly name alternatives or when-not-to-use, so it stops short of a 5, but the context is clear enough for an agent to select it.

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