hold_button

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

With no annotations provided, the description carries the full burden of behavioral disclosure. It clearly describes the tool's behavior: holding a button for an extended period and returning a screenshot. It specifies the default duration (30 frames, ~500ms) and mentions the return value (screenshot). However, it doesn't mention potential side effects like game state changes or whether this affects other operations.

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 perfectly structured and concise. The first sentence states the core functionality, the second differentiates from siblings, and the parameter section clearly explains each argument. Every sentence earns its place with no wasted words, and the information is front-loaded with the most important details first.

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 2-parameter tool with no annotations and no output schema, the description does an excellent job covering the essentials: purpose, differentiation, parameters, and behavior. The only minor gap is that while it mentions returning a screenshot, it doesn't describe the format or content of that screenshot. Given the tool's relative simplicity, this is a strong description.

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?

With 0% schema description coverage, the description fully compensates by explaining both parameters. It defines 'button' as 'The button to hold' and 'frames' as 'Number of frames to hold' with a default value and time conversion. The description adds meaningful context about what these parameters mean in practice, going beyond what the bare schema provides.

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 the tool's purpose with a specific verb ('hold') and resource ('button'), and explicitly distinguishes it from its sibling 'press_button' by explaining it's designed for longer holds. The description provides concrete examples of use cases like walking multiple tiles or fast-forwarding text with B held.

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 explicitly states when to use this tool versus alternatives by directly comparing it to 'press_button' and specifying it's for 'longer holds'. It provides clear context about appropriate use cases (walking multiple tiles, fast-forwarding text) and implicitly suggests when not to use it (for short button presses).

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