Browser Page Stats

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

No annotations are provided, so the description carries the full behavioral burden. It discloses the 'cheap' cost profile and that values are 'approximate', which manages agent expectations about precision. Missing operational details like auth requirements or rate limits, but for a read-only stats tool the key trait (cheapness/purpose) is communicated.

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 sentences, front-loaded with the tool's value proposition, then immediately followed by actionable guidance. Every clause earns its place with zero filler.

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?

Complete enough for a 2-param, zero-required pre-check tool with no output schema. The description tells the agent what metrics come back and how to act on them, though it doesn't specify the return format (e.g., whether stats are numbers or objects), which is a minor gap for a tool with no output schema.

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 coverage is 100%, so the schema already documents mode and sessionId fully, including the enum and the headless-session relationship. The description adds no parameter information beyond what the schema provides, so the baseline 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?

States a specific verb+resource (cheap pre-check for page size/complexity) and enumerates exactly what it returns (DOM node count, HTML length, visible-text length). This clearly distinguishes it from browser_get_dom, browser_snapshot, and browser_extract by naming them as alternatives.

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?

Explicit when-to-use: 'Call this BEFORE browser_get_dom on an unfamiliar page.' Also gives the decision tree: whether a full dump is safe, whether to scope with selector/maxLength, or whether to use browser_snapshot/browser_extract instead. This is textbook routing guidance.

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