edit_screen

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

With no annotations available, the description must fully disclose the tool's behavior. It only says 'edit', implying a mutation, but does not mention side effects, reversibility, permissions, or what happens to the screen after editing. This is insufficient for a potentially destructive operation.

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 with no fluff. It efficiently states the action and target, making it appropriately concise for the tool's purpose.

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 the schema covering parameters, the description lacks essential context about how the text prompt is interpreted, the role of optional modelId/deviceType, and what the edit operation entails. For a tool that modifies an existing screen, this is not sufficiently complete for an agent to understand the full workflow.

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 input schema fully describes all 5 parameters (100% coverage), including enums for modelId and deviceType. Since the schema already provides the necessary parameter semantics, the description does not add value here, so the baseline of 3 applies.

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 action ('Edit'), the resource ('an existing screen'), and the method ('using a text prompt'). The word 'existing' implicitly differentiates it from sibling tools like generate_screen, making its purpose unambiguous.

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 provided on when to use this tool versus alternatives such as generate_screen, nor are any preconditions or exclusions mentioned. The description only states what the tool does, not the appropriate context for its use.

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