ui_assert

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

No annotations are provided, so the description must carry the full burden of behavioral disclosure. It only states that the tool checks visibility and text, but gives no information about what happens on assertion failure, whether it interacts with a browser session, or any side effects. This is insufficient for an agent to understand the tool's runtime 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?

The description is a single concise sentence that is front-loaded with the core idea. It is efficient and easy to parse, though it is too brief to convey essential details. The structure is appropriate for a simple tool, but the content is under-specified.

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?

Given the tool has 5 parameters, no annotations, no output schema, and no schema descriptions, the description is severely incomplete. It does not explain what selector means, how timeoutMs behaves, or what the return value or success/failure semantics are. An agent cannot reliably use this tool based solely on this description.

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?

The schema has no descriptions for any of the 5 parameters, and the tool description only adds 'visibility and text', which loosely maps to visible and textContains. The critical parameters selector, sessionId, and timeoutMs remain completely unexplained, leaving the agent without understanding how to invoke the tool correctly.

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 uses a specific verb 'Assert' with a clear resource ('UI conditions') and narrows the scope to 'visibility and text'. This distinguishes it from sibling tools like ui_action (which performs actions) and ui_extract (which extracts data).

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 provides no guidance on when to use this tool versus alternatives. It merely states the generic purpose without any context about when assertions are appropriate or how it differs from other UI tools. The usage is only implied by the verb 'Assert'.

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