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

With no annotations provided, the description carries the full behavioral burden. It discloses the native clearing mechanism, the focused-field behavior versus targeted-field behavior, the expected workflow, and the session auto-start behavior. It does not cover failure cases or return values, but it provides meaningful behavioral context beyond the schema.

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 three sentences with no filler. It front-loads the core purpose, then gives the key parameter behavior, the recommended workflow, and the session requirement. Every sentence earns its place and avoids repeating schema field descriptions.

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?

The description is largely complete for an action tool with no output schema: it explains what to clear, how to choose between focused and labeled fields, the expected workflow, and the session requirement. The main gap is the absence of error behavior when no field is focused and no label is provided, but the provided context is sufficient for correct invocation in most cases.

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 important semantics beyond the schema by explaining that omitting `label` clears the focused field and that tapping the field first is part of the pattern. It does not expand much on `type` or `strategy`, but the schema already documents those adequately.

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 states a specific verb ('Clear'), a resource ('a text field on an iOS device'), and a precise mechanism ('native element-clear command'). It distinguishes itself from a common alternative ('unlike sending backspaces') and from the related ios_send_keys workflow, making it easy for an agent to see exactly what this tool does.

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?

It gives clear usage context: omit `label` to clear the focused field after tapping it, or pass `label` to target a specific field. It also provides a workflow pattern ('tap field → ios_clear_text → ios_send_keys'). However, it does not explicitly name alternatives or exclusions, such as when a generic clear tool or a different iOS command would be preferred.

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