Type

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

With no annotations, the description bears full responsibility for behavioral disclosure. It states the core action but omits important details such as whether existing text is cleared, whether events are triggered, or how errors are handled. The description is too sparse 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, front-loaded sentence that efficiently conveys the tool's purpose. Every word adds value, with no redundancy or filler.

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 simple typing action, the description is minimally adequate but lacks information on return values, error conditions, and behavior with different input types (e.g., textarea vs input). With no output schema, the agent must infer results.

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 already provides descriptions for 75% of parameters (ref, element, sessionId). The description adds context that ref comes from a snapshot, but does not elaborate on the 'text' parameter (no schema description) or the 'element' parameter beyond its human-readable purpose. It adds marginal value over 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's action ('Fill an input with text') and specifies the resource (an input) and the source of the element reference ('by ref from browser_snapshot'). This distinguishes it from sibling tools like browser_click or browser_fill_form.

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 implies usage after taking a snapshot (by mentioning 'from browser_snapshot'), but it does not explicitly state when to use this tool vs alternatives like browser_fill_form or browser_press_key. No usage restrictions or prerequisites are provided.

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