safari_switch_tab

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

With no annotations provided, the description must carry the behavioral burden, and it does: it discloses that Safari is not focused, that the operation changes the logical session target, and that receipt precedence over index is intentional. It does not describe invalid-receipt behavior or what happens when neither parameter is supplied, but the core behavioral traits are present.

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 with no filler. The most important behavior is front-loaded, the parameter mechanics are compactly explained, and the 'Rarely needed' guidance is placed last as a useful caveat rather than clutter.

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 small, rarely needed tool with no output schema, the description covers the main invocation paths, precedence, and the fact that it does not focus Safari. It could briefly mention how to obtain an index or receipt, but the core information an agent needs to call it correctly is present.

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 coverage is 100%, so the schema already documents all three parameters. The description adds meaningful semantics beyond the schema by clarifying how the two targeting mechanisms relate: index is scoped to the current session window, receipt recovers across windows, and a valid receipt supersedes an index. This is useful selection guidance for an agent deciding what to pass.

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 states a specific action ('Switch the MCP session's logical target') and explains the two supported inputs: an index for the current session window or an opaque receipt to recover an owned tab. It also distinguishes this from navigation and tab-management siblings by noting it acts 'without focusing Safari' and that the receipt identifies the exact owned tab across windows.

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 gives clear context: use an index for the current window, or a receipt to recover a tab across windows, and notes that a valid receipt takes precedence. It also explicitly says the tool is 'Rarely needed' because passing a receipt on each call already targets that tab, which provides a useful when-not-to-use signal, though it does not name alternative sibling tools directly.

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