type

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

No annotations are provided, so the description carries the full behavioral burden. It does disclose the meaningful trait that typing is per-character and fires key events, but says nothing about focus/visibility prerequisites, timing/speed, or failure behavior when the selector does not match a typeable element.

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 short sentence with no filler, front-loading the action and then the behavioral mechanism. Every clause earns its place.

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 simple two-parameter tool with full schema coverage and no output schema, the description is nearly sufficient. The only meaningful gap is that per the sibling set (focus, visibility, special keys) an agent could benefit from knowing prerequisite element state.

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% and both parameters ('selector', 'text') are documented in the schema, so the description only needs to avoid contradicting it. It adds no extra meaning such as selector match scope or whether text may contain special keys (e.g., Enter/Tab), 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 and resource ('Type text') plus a distinguishing mechanism ('character by character, triggers key events'). This implicitly separates it from the sibling 'fill', which is presumed to set values directly, though the sibling is never named.

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 parenthetical '(triggers key events)' hints at when this is preferred over a direct value-set such as 'fill' (e.g., inputs needing keystroke events), but usage is only implied. No explicit when-to-use, when-not-to-use, or named alternative is given.

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