Set Visual Spec

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

Annotations already indicate this is a mutating operation (readOnlyHint: false, idempotentHint: false, destructiveHint: false), and the description adds the context of setting a baseline. However, it does not disclose important behavioral details such as whether setting a spec overwrites an existing one, whether file_path and screenshot are mutually exclusive, or what happens after setting. With annotations present, the description provides some added value but not rich behavioral context.

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, concise sentence that front-loads the main action ('Set') and contains no filler. Every word contributes meaning, and it is immediately scannable. This is an exemplary level of conciseness.

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 setter tool with only three parameters and a complete parameter schema, the description covers the basic purpose but lacks additional context such as how the baseline is used, whether it replaces existing baselines, or what the expected outcome is (though no output schema exists). It is adequate but leaves some gaps for an agent to fully understand the tool's role in the larger 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 has 100% description coverage for all three parameters (name, file_path, screenshot), so the baseline is 3. The description itself does not mention any parameters or add extra meaning beyond the schema, so it neither improves nor detracts from what the schema already provides.

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 ('Set a screenshot or mockup design as a Visual Spec baseline') and its purpose ('for UI compliance testing'). It uses a specific verb and resource, making the tool's role understandable. However, it does not explicitly differentiate from sibling tools like 'save_visual_snapshot' or 'create_visual_blocker', so it stops short of a 5.

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 in the context of UI compliance testing, giving some context about when to use it. However, it does not provide explicit guidance on when to choose this tool over alternatives (e.g., 'save_visual_snapshot') or any exclusions. The 'for UI compliance testing' phrase is the only usage signal, making it borderline between implied and clear context.

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