Find the reads behind a page

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

Annotations already mark it read-only and open-world, and the description adds genuinely new limits: only successful page-fetch and XHR reads are captured while native, IPC and service-worker traffic is invisible. That coverage gap is the key behavioral fact an agent needs before trusting a negative result; only the return format/pagination detail is missing.

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?

Three short sentences with zero filler, front-loaded with the mechanism and output, then the hand-off, then the limitation. Every sentence earns its place.

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?

With no output schema, the description carries the burden of describing results and does so ('lists the JSON GET requests'), plus a caveat about what it misses. It could say more about ordering, volume, or how signed-in state affects visibility, but an agent has enough to call it correctly.

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 durationMs, url and storageState are already documented, but the description still adds meaning by tying capture to the page-load window ('while it loads'), clarifying what durationMs governs. Marginal but real value on top of the schema.

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?

The description states a specific verb and resource ('Opens a page in headless Chromium and lists the JSON GET requests it makes while it loads') and scopes the output to JSON GET reads, which clearly separates it from siblings like compare_reports or verify_change.

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?

It gives an explicit downstream use: 'Use it to choose the endpoint for check_read_recovery,' which tells the agent when this tool precedes another. There are no explicit when-not conditions or named alternatives beyond that hand-off, so it stops short of a 5.

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