Get Current Tab

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

Annotations already establish that the tool is read-only, idempotent, and non-destructive, so the bar for extra behavioral disclosure is lower. The description adds the fallback resolution behavior: the agent's current tab, or the active tab if the agent has none. This is useful context beyond the annotations.

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 with a colon separating the core action from the fallback explanation. Every word earns its place, and there is no filler or repetition beyond what the schema already conveys.

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, read-only, idempotent tool, the description plus annotations cover safety profile, default behavior, and parameter handling. The main unstated detail is the exact shape of the returned tab object, but that is minor given the simple purpose.

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 already covers the single parameter tab_id fully, including the omit behavior. The description essentially restates the schema's meaning ('a call with no tab_id') rather than adding new parameter-level detail, so it meets the baseline but does not exceed it.

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 and resource: 'Get the tab a call with no tab_id would act on.' It clearly identifies the tool's unique role as resolving the default tab target, distinguishing it from siblings like list_tabs and get_page_content.

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 for when to use the tool: to determine which tab an action would affect when no tab_id is provided. It does not explicitly name alternatives or state when not to use it, but the default-target framing is enough to guide an agent.

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