Accept or dismiss a page prompt

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

Annotations only give readOnlyHint=false; the description adds the real behavioral payload — that the page remains blocked until this is called, that accept maps to OK/Cancel, and that a "no such alert" error is a normal, non-failure outcome. That last point meaningfully prevents the agent from treating a benign error as a fault. It doesn't say what the tool returns or whether dismissing a confirm discards unsaved state.

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?

A single tight block: purpose first, then parameter meaning, then the failure/blocking consequence. Every clause carries information and nothing is redundant.

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 three-parameter dialog tool with no output schema, the description covers purpose, both meaningful parameter behaviors, and the blocking/error semantics. Only the return value and any post-dismiss state effects are left implicit, which is a minor gap here.

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%, so accept, context and userText are already documented in the schema. The description restates accept and userText semantics without adding new detail and never mentions the context parameter. Baseline 3 applies when the schema carries the parameter burden.

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 (answer/accept/dismiss) and a specific resource (a page prompt: alert/confirm/prompt), and even names the underlying BiDi command. It is clearly distinguishable from the other browser tools, though it never names its closest sibling browser_list_prompts, which an agent might otherwise reach for to inspect pending dialogs first.

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?

"Without this the page stays blocked" gives a clear condition for when the tool is required, which is exactly the decision an agent needs. It stops short of naming alternatives (e.g. browser_list_prompts to see what is waiting) or of saying when not to call it.

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