css_computed_style

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

No annotations are provided, so the description carries the full burden. It communicates a read-only 'get' operation, but gives no details about return format, behavior with invalid selectors, or whether computed values update live. It adds minimal behavioral context beyond the verb itself.

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 sentence, front-loaded with the action and resource, and contains zero wasted words. It immediately communicates both the core capability and the optional filtering behavior.

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?

This is a simple tool with only two parameters, but there is no output schema and no annotations. The description omits the return shape (e.g., a map of property names to values), which the agent may need to plan subsequent steps. It is acceptable but not fully complete for a tool without an output schema.

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?

Schema description coverage is 100%, with both 'selector' and 'properties' fully documented in the schema. The description only rephrases the optional property filtering ('Optionally filter to specific properties') without adding new semantic details, so the baseline 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 uses a specific verb+resource: 'Get computed CSS styles for an element.' The term 'computed' clearly distinguishes this tool from sibling rule-inspection tools like css_matched_rules and css_background_colors, making the purpose immediately clear.

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 css_matched_rules or other style-related tools, nor does it specify contexts (e.g., after layout changes) where computed styles are preferred. Usage context is entirely absent.

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