click_ui

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

With no annotations, the description carries the full burden and delivers extensively: the click goes through the real pointer with visible cursor and 'same panic-kill guarantees', the window is focused first (a side effect), ambiguous names return candidates instead of guessing, the tool auto-falls back when no tree exists, and `allow_auth=true` overrides a refusal to click system authentication dialogs — a major safety-relevant behavior.

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 dense paragraph where every clause earns its place — mechanism, disambiguation, fallback, `then`, and auth override are all covered without filler, and the core action is front-loaded in the first clause. It is slightly run-on and would benefit from visual separation, but nothing is redundant.

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 an 8-parameter tool with zero schema parameter descriptions, this is quite complete: core action, matching semantics, ambiguity resolution, no-tree fallback routing, `then` behavior, and auth-dialog safety are all present. An output schema exists, so return values are covered by structured data. The only material gaps are `button` and `double` semantics.

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 0%, so the description must compensate. It adds real semantics for six parameters: `name` matching (exact preferred, substring otherwise), `mark` sourced from the last `marks` capture, 0-based `index` for disambiguation, all four `then` values with the 'ui' effect explained, and `allow_auth` overriding the auth-dialog refusal. However, `button` and `double` are left undocumented — their defaults hint at meaning but the description adds nothing.

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: 'Click a control by its accessible NAME, or by a mark number', and explains the mechanism (coordinate from the accessibility tree, window focused first, real pointer). The phrase 'no screenshot and no pixel estimation is spent' explicitly distinguishes it from the screenshot/zoom/pointer workflow among its siblings.

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 explicit when-to-use (click by accessible name or mark in one call) and explicit when-not: 'Falls back with a note when the app exposes no tree (use screenshot + zoom + pointer then)', naming the alternatives. It also instructs to pass exactly one of `name` or `mark`, and explains when `index` should be supplied.

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