Type

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

With no annotations provided, the description bears full responsibility for behavioral disclosure. It states the action ('set the text value') but omits relevant side effects such as whether it replaces the entire existing value, requires focus, or errors when the selector isn't found. The minimal disclosure is insufficient for a mutation tool.

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, focused sentence with no filler. It front-loads the core action and matching criterion. While it might be considered under-specified, it is appropriately concise for a simple tool.

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 tool with 3 parameters, no output schema, and no annotations, the description is too sparse. It doesn't clarify the optional 'window' parameter, behavior on selector miss, or how the text is applied (replace vs append). The agent lacks critical details for reliable invocation.

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 only 33% (only 'selector' has a description). The description does not explain the 'text' parameter (required) or the optional 'window' parameter, and its mention of 'field matched by selector' only hints at the selector role. With low schema coverage, the description should compensate but doesn't.

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 ('set') and resource ('text value of a field') with a clear matching mechanism ('by selector'). It is distinct from siblings like 'click' or 'invoke_action' because it explicitly targets text input, though it doesn't name an alternative to disambiguate.

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 guidance is given on when to use this tool versus alternatives like 'click' or 'invoke_action'. There is no mention of prerequisites (e.g., field must be visible/focused) or exclusionary conditions, leaving the agent to infer applicability from the name and description alone.

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