screen_register

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

With no annotations, the description must disclose behavioral traits. It mentions 'add or replace' but does not explain what replace does to existing data, whether it is idempotent, any validation side effects, or return values. The behavioral implications are largely opaque.

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?

A single sentence that is front-loaded with the primary action and efficiently lists key components without filler. It is concise and well-structured.

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 tool has a highly complex nested schema, and the description provides only a partial overview. It covers the required fields and components, but omits the required 'id' and other important optional properties. It gives enough context for a high-level understanding but relies heavily on the schema for full details.

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's only parameter 'screen' has a generic description ('The screen definition'), so the tool description adds some meaning by listing fields like intent, requiredStates, and designedStates. However, it omits many other properties (layout, rationale, exemptions) and does not fully clarify the parameter's structure beyond 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 action 'Add or replace a screen' with a specific object, and enumerates key fields (intent, requiredStates, designedStates, components). However, it does not explicitly distinguish this tool from siblings like screen_critique, so it misses full differentiation.

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 does not mention prerequisites, contexts, or exclusions. The only implied usage is the basic action of adding or replacing a screen, which is just the purpose restated.

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