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

With no annotations, the description carries the full burden and does so richly: sessions survive between calls and across days, {{secret:NAME}} values are typed only on that secret's allowed hosts and redacted from replies, handoff types the code without returning it, and the sandbox allowance (3 live, 60 min/day free) is disclosed.

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?

It is a dense single block, but the differentiator (persistent headless Chrome) is front-loaded and every clause carries information. Slightly better formatting of the action list would help, but there is little 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?

For a 13-parameter tool with no annotations and no output schema, it covers return values (url, title, page text, links), persistence semantics, secret handling, rate limits, and the escalation path. The remaining gap is the undocumented top-level tuning params such as max_text and wait_s.

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?

At 0% schema description coverage the description must compensate, and it documents the steps sub-actions (goto, click, fill, type, press, select, wait_for, wait_ms, scroll, back, extract, eval, screenshot, clear_cookies) plus handoff's kind/note/fill/submit and the {{secret:NAME}} fill syntax. But top-level params like max_text, wait_s, text, and links go undocumented, leaving a significant gap.

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 resource and mechanism: a real headless Chrome per named session with enumerated actions (open, run, screenshot, pause, kill, list, handoff). An agent can distinguish it from fetch (static retrieval) and handoff (human escalation) without opening the schema.

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?

Gives a concrete conditional route — 'Stuck on 2FA? action handoff' — and implies use when logins/cookies/tabs must persist across calls. However, it never explicitly contrasts with sibling fetch for simple static requests, so the when-not guidance is inferred rather than stated.

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