ui_find

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

Annotations already declare readOnlyHint=true, destructiveHint=false and openWorldHint=true, so the description's main contribution is the visibility restriction and the security boundary (no JS evaluation, no credential values) — genuine added context. It does not disclose return shape, whether a missing selector errors or returns empty, or why idempotentHint is false for an ostensibly read-only lookup.

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 front-loaded clause with zero filler; the verb, resource and mechanism land first. It is however compressed to the point of omitting operational detail rather than being a model of tight structure.

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 4-parameter browser-interaction tool with no output schema, the description should say what it returns (matching elements? count?) and how target_id and expected_layout_id affect the call. The mismatch-guard and tab-target requirements live only in the schema, leaving the agent without the precondition narrative needed to invoke this reliably.

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 75%; selector, target_id and expected_layout_id are each documented inline. The description adds only that matching is limited to visible elements, which is meaningful semantics beyond the schema, but it says nothing about `limit` or the pagination/truncation behavior.

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 ("Find visible elements") plus the mechanism (CSS selector), which cleanly separates it from ui_snapshot and ui_read. It never names a sibling or explains how it differs from ui_list_dialogs/ui_list_panels, so differentiation is left partly inferential.

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?

There is no explicit when-to-use, no prerequisite (e.g. obtain target_id from browser_list_tabs first), and no named alternative for cases where a selector is unavailable. The only guidance is a negative constraint ("no arbitrary JavaScript or credential values"), which hints at scope but not at tool selection.

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