ui_check

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

With no annotations provided, the description carries the full disclosure burden and delivers: it reads the current state first, clicks only if it differs, and is therefore idempotent across repeated calls. This is exactly the behavioral insight an agent needs to avoid double-calling and to predict the outcome of a second invocation, going well beyond any structured field.

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 sentences with zero filler: the first front-loads the action and operand scope, the second explains the mechanism and the pitfall it avoids. Every clause earns its place, including the concrete example of why a naive toggle fails.

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 9-parameter tool with no annotations and no output schema, the description covers purpose, operand scope, and the crucial idempotency behavior. The remaining gaps are minor: return values, timeout/no-match failure behavior, and explicit routing among the many sibling ui_* tools.

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% — all 9 parameters carry individual descriptions — so the baseline of 3 holds even though the tool description itself adds no per-parameter meaning. The central 'checked' parameter is adequately covered by the schema ('The state you want'), consistent with the declared purpose.

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 — 'Set a checkbox or radio to a specific state' — and contrasts with 'toggling blindly', distinguishing it behaviorally from generic click/toggle helpers among the siblings (notably ui_click). The purpose is unmistakable before reading any schema.

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 gives clear context for when this tool is the right choice: when a control must reach a deterministic state, and why it beats a 'toggle' helper that can leave the form in the wrong state. It doesn't explicitly name an alternative tool or state exclusions (e.g., 'use ui_click for non-form controls'), so it stops short of full routing guidance.

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