Find Element

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

Annotations already declare readOnlyHint, openWorldHint, idempotentHint, and non-destructive behavior. The description adds selector interpretation behavior (bare selectors are CSS, text: prefix) but doesn't mention return behavior, timeout defaults, or scoping with frames/shadow roots. With annotations covering the safety profile, this is acceptable but minimal.

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 concise sentences that front-load the core purpose and immediately give a useful syntax rule. No wasted words.

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 schema is rich with frames, shadow hosts, and an accessibility target mode, but the description only mentions CSS/XPath and text matching. It omits the accessibility role/name target kind and frame/shadow scoping hints, relying heavily on the schema to communicate the full capability set.

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%, so the schema already documents the selector and timeout parameters. The tool description repeats the selector syntax already present in the schema (bare=CSS, text:...), adding no additional parameter meaning beyond the schema.

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 clearly states the tool finds an element on the page using CSS selectors or XPath, which is a specific verb+resource. The singular 'an element' distinguishes it from element_find_all, and the syntax rule for bare selectors vs text: adds precision.

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?

No explicit guidance on when to use this tool versus alternatives like element_find_all. The only usage guidance is about selector syntax, not about choosing the right tool for a scenario.

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