Send simultaneous Android keys

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

The description adds behavioral context about explicit ordering and chord duration beyond the annotations, but lacks details on error handling, blocking behavior, or prerequisites.

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 concise sentence that immediately conveys the tool's purpose, with no extraneous words.

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?

Given the complexity of 5 parameters and required params, the description is adequate but does not fully cover usage context such as valid key values or expected behavior for invalid inputs. Output schema exists but is not referenced.

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 description coverage is only 40%, and the description does not provide additional meaning for parameters like keys, source, or durationMs beyond the brief schema 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 clearly states the tool injects a device-supported key combination with explicit ordering and chord duration, distinguishing it from single-key tools like mobile_input_key.

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 usage for simultaneous key combinations through the title and name, but does not explicitly state when to use this tool versus alternatives like mobile_input_key or mobile_input_tap.

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