page_type

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

With no annotations, the description carries the burden and does disclose human-like key events and the success return value. However, it does not explain failure behavior, whether text is appended or replaces existing content, or any focus/visibility requirements.

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 three sentences with no filler. It front-loads the core operation, then gives routing guidance and the return value, so every sentence earns its place.

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 description covers the core purpose, the main alternative, and the return value, which is useful given no output schema. But with no annotations, it leaves operational gaps around error handling, content replacement, and preconditions that would be needed for fully confident 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 description coverage is only 25%, and the description does not sufficiently compensate. It adds minimal meaning for 'text' and 'selector', but session_id and page_id remain unexplained, and selector semantics mostly repeat the schema's existing 'CSS selector' note.

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 states a specific action: typing text character-by-character into an element by CSS selector with human-like key events. It explicitly distinguishes this tool from page_type_ref, making the purpose and scope clear even without a title.

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?

It gives explicit guidance: 'Prefer page_type_ref when you have a page_a11y ref' and 'Use this only when you only have a CSS selector and don't need rich editor support.' This clearly tells the agent when to use this tool versus the main alternative.

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