send_text

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

With no annotations, the description carries the full behavioral burden, and it does disclose one genuinely useful limitation (no Chinese support). However, it omits other important traits: whether text appends to or replaces existing content, whether the target must be in the foreground, and whether it requires focus to be set first.

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?

Two tight sentences, front-loaded with the primary action and immediately followed by the critical limitation. No filler or 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?

An output schema exists, so return values need not be explained. For a simple one-parameter text-input tool the description is largely sufficient, though the missing focus prerequisite and append/replace behavior leave small gaps.

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 100% for the single parameter, so the schema already documents 'text_to_send'. The description adds nothing about format, length limits, or escaping beyond what the schema provides, making the baseline 3 appropriate.

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 (send text via simulated keyboard) and the precise resource/target (the currently focused input box). This clearly distinguishes it from the touch-oriented siblings like tap_screen, long_press, and swipe_screen, which manipulate coordinates rather than text content.

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?

Gives a clear when-not condition plus an alternative: Chinese text is unsupported and should go through another input-method approach. It does not, however, state the prerequisite that the target input must already be focused (via tap_screen), which an agent needs to sequence calls correctly.

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