check_webkit_compatibility

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

Despite no annotations, the description details the tool's behavior: extracting all CSS properties, running CSS.supports(), and reporting unsupported properties, missing prefixes, and rendering quirks. It does not address potential side effects or performance, but as a read-only check, it is well-explained.

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 two sentences, front-loaded with the main purpose, and every sentence is informative without redundancy or fluff.

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?

Given no parameters and no output schema, the description is mostly complete, covering the tool's actions and results. It lacks explicit details about the output format, but the context is sufficient for understanding the tool's purpose.

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?

With no parameters, schema coverage is 100%, so baseline is 3. The description adds value by explaining what the tool does beyond the empty schema, providing meaningful context about the analysis performed.

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 checks CSS compatibility against a live Safari session, using structured DOM APIs and CSS.supports(). It distinguishes itself from sibling tools like get_computed_style by specifically targeting compatibility issues.

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 use when verifying CSS compatibility in Safari, but does not explicitly mention when not to use it or provide alternatives. The context is clear but lacks exclusions.

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