Retrieve the current web address of a browser tab to identify the active page, with optional tab selection and request timeout.
Current URL.
| Name | Required | Description | Default |
|---|---|---|---|
| tab | No | tab id, defaults to current | |
| request_timeout | No | Outer page request deadline in milliseconds; defaults to at least 30000 |
Changes observed during successful MCP inspections.
v0.1.0Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
No annotations are provided, so the description carries the full disclosure burden, and it discloses nothing: no statement that it is a side-effect-free read, no return format (string? object with tab id?), no note on how the `tab` default resolves, and no behavior when no tab/page is loaded.
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?
Two words is not conciseness, it is under-specification; there is no front-loading problem but also no content that earns its place. The brevity removes information rather than waste.
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?
In a 40+ tool browser automation suite, an agent needs to know this returns the current page URL (a read) versus navigating to one, and how it interacts with the `tab` parameter. With no output schema and no annotations, the description leaves all of that unaddressed.
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 100% — the schema already explains `tab` (defaults to current) and `request_timeout` (deadline in ms). The description adds nothing beyond the schema, so the baseline of 3 applies.
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?
"Current URL." is essentially a restatement of the tool name with no verb or stated action — it never says it *returns/reads* the URL of the page or tab. Among siblings like `navigate` (which sets a URL) and `html`/`text`/`title` (which return page content), an agent can infer the read semantics but only by guessing.
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?
No when-to-use, when-not-to-use, or alternative is named. It does not distinguish itself from `navigate` (URL mutation) or `new_tab`/`switch_tab`/`tabs` (tab addressing), which is the exact ambiguity an agent would face here.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.