select_tab

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

With no annotations, the description carries the whole burden: it usefully discloses the ordering dependency and a separate consent/approval requirement, which go beyond the schema. It does not explain what selection actually changes for subsequent calls, whether other tabs are affected, or what happens if the selector matches nothing or several tabs.

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?

Three short sentences, front-loaded with the action and prerequisite, then the parameter note; nothing is wasted. The 'selector:' label style is slightly terse but readable.

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 one-parameter tool without annotations or an output schema, the definition covers prerequisites and parameter sourcing but leaves out what a successful selection means for later calls and what failure looks like. Adequate but with visible gaps.

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 supply the meaning, and it does: 'selector' is either the index returned by list_tabs() or a unique url/title substring. The only gap is the 'unique' qualifier — no guidance on ambiguity resolution or error behaviour when multiple tabs match.

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?

States a specific verb and resource ('Select one tab') and anchors it to the attach_browser step, so the agent can place it in the browser workflow. It does not explicitly contrast itself with list_tabs as a choice, but it names list_tabs as the source of selectors, which clarifies the division of labour.

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?

Gives a clear prerequisite ('after attach_browser()') and a clear gating condition ('Requires its own scoped reflex_ask approval'), which is exactly the when-to-use context an agent needs before calling. It stops short of stating when not to call it or what to do if the selector is ambiguous, so it is not a full 5.

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