agentest_get_ui_tree

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

No annotations exist, so description must disclose behavior. It explains that each call returns a fresh snapshot, refs can become stale with clear errors, and provides output formats. Could mention that it's read-only and has no side effects, but sufficient for safe invocation.

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?

Well-structured with bullet points for options. First sentence could be tighter but is effective. Every sentence adds value without redundancy. Awarding 4 due to minor verbosity in the introductory sentence.

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?

Despite no output schema, description explains return formats (compact text with @refs, full JSON tree). Covers error conditions (stale refs) and usage patterns. Lacks details on bounds/classNames in full format, but sufficient for agent to understand output.

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 covers all 3 parameters with descriptions. The tool description adds value by explaining defaults ('compact'), usage tips ('use full for debugging'), and context for options ('onlyInteractive drops plain text'). Descriptions enhance beyond schema alone.

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 fetches a fresh UI screen snapshot with compact text by default. It distinguishes from sibling tools like screenshot (visual) or device_info (metadata) by focusing on interactive element hierarchy and refs.

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?

Provides clear guidance on when to call this tool (to get fresh refs) and how to use refs in selectors with error handling. Lacks explicit when-not-to-use or comparison with alternatives, but usage context is well implied.

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