Get Current Safari URL

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

The annotations already declare readOnlyHint and idempotentHint, so the agent knows this is a safe, idempotent read. The description adds the specific output (URL and title) but does not disclose edge cases like behavior when Safari is not running or when no tab is active. Given the annotation coverage, this is a reasonable level of transparency, similar to the TDQS 4.3 calibration case.

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, front-loaded sentence: 'Gets the URL and title of the current/active Safari tab.' Every word earns its place, with no redundant or missing information. It is appropriately concise for the tool's simplicity.

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 tool with no parameters, good annotations, and a clear return value (URL and title), the description is fully complete. The sibling tool list provides additional context for disambiguation. No output schema exists, but the description sufficiently explains what the agent can expect. The simplicity of the tool makes further detail unnecessary.

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 zero properties, so there are no parameters to describe. According to the rubric, a baseline of 4 is appropriate for zero-parameter tools. The description adds no parameter details, but none are needed since the tool takes no input.

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 function: 'Gets the URL and title of the current/active Safari tab.' The verb 'gets' and the specific resource ('current/active Safari tab') make the purpose obvious and distinguish it from sibling tools like list-safari-tabs or open-safari-url.

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 when to use the tool (when you need the current/active tab's URL/title) but does not explicitly mention alternatives or exclusions. It would be stronger if it noted that list-safari-tabs should be used for obtaining all tabs, but the context is generally clear from the name and description.

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