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

With no annotations, the description carries the full burden; it does add useful context by disclosing a cost of 1 mcp_call, which is genuine behavioral value. However it omits that a live browser session is required, how the 'described area' is resolved (vision/LLM locating), and what happens if the area cannot be found.

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, zero filler, purpose front-loaded followed by the cost constraint. Every clause carries information.

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 browser tool with no annotations, no output schema, and no documented parameters, the definition leaves critical gaps: session prerequisite, return shape (string vs. structured excerpts), and failure behavior when the described area isn't found.

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 compensate and largely fails. 'Described area' faintly implies area_description is natural-language, but nothing explains the expected phrasing, granularity, or the 'session' parameter's role and default.

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 concrete verb+resource: 'Extract text from a described area of the page.' An agent can infer it differs from browser_get_html (full HTML) and browser_screenshot (image), but the description never names those alternatives explicitly.

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 guidance on when to prefer this over browser_get_html, browser_screenshot, or browser_click flows. The only usage-adjacent detail is the cost note ('Costs 1 mcp_call'), which hints at a tradeoff but doesn't tell the agent how to weigh it.

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