switch_tab

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

With no annotations provided, the description carries the full behavioral disclosure burden, and it does so well. It explicitly states that switching the tab does not focus the browser, that the setting applies to later calls, and how ambiguous URL matches are resolved. These are non-obvious behavioral traits an agent needs to avoid mistakes.

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 long, front-loaded with the primary purpose, and contains no filler. It packs the key behavioral constraint and the alternative tool mention into the second sentence without being verbose.

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 stateful tab-selection tool with no annotations, no required parameters, and an output schema present, the description is complete. It covers selection methods, ambiguity handling, the no-focus side effect, and when to switch to activate_tab. Nothing critical is missing for an agent to call it correctly.

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 0%, so the description must compensate, and it does. It explains all four parameters: browser name, session_id, url_pattern, and activate. It even adds matching semantics: a URL substring must match exactly one tab, otherwise use the full session_id. This goes well beyond the bare schema.

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 purpose: 'Set the target tab for later calls' using session id, URL substring, or browser name. It also distinguishes itself from activate_tab by explicitly noting that this tool does not focus the browser. This gives an agent a precise mental model of what the tool does.

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 actionable when-to-use guidance, including when to pass a session_id ('pass its full session_id when several tabs match') and when to use an alternative ('Use activate=true or activate_tab when foreground work is required'). It also says the URL substring must match exactly one tab, which is a clear constraint on usage.

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