Replace sky

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

Annotations already provide non-read-only and open-world hints. The description adds that the tool returns a new image URL, which is helpful, but does not disclose other behaviors like auth requirements, rate limits, or side effects beyond what annotations imply. No contradiction with annotations.

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 extremely concise, using two short sentences. The first sentence states the purpose, and the second states the return value. No wasted words.

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 tool with two parameters and no output schema, the description covers purpose and return value adequately. It could mention that skyStyle is optional or provide examples, but overall it is complete enough.

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 already covers both parameters with descriptions (100% coverage), so the description adds no additional semantic value. Baseline 3 is appropriate.

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 ('Replace a dull or overcast sky with a clear blue one') and specifies the resource (sky). It distinguishes itself from sibling tools like pedra_remove_object and pedra_enhance by focusing on a specific transformation.

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 indicates when to use the tool (dull or overcast sky) but does not explicitly state when not to use it or mention alternatives. The context is clear but lacks exclusionary guidance.

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