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

Adds substantial context beyond the annotations: robots.txt is respected, nothing is stored server-side (stateless), number-only changes can be suppressed, and the token carries the setting forward. It also discloses the pricing model ($0.002 USDC via x402 or prepaid credits, free trial), which an agent needs to decide on invocation.

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?

Core purpose and protocol are front-loaded, and each sentence carries information. The trailing pricing/trial sentence is useful for an x402 tool but slightly extends the block beyond the core mechanic.

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?

An output schema exists, so return values need not be documented, yet the description still summarizes the response (yes/no plus added/removed blocks). Combined with the stateful protocol and cost disclosure, an agent has everything required 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 already 100%, so the baseline is 3, but the description adds the sequencing semantics of `token` (omit on first check, send on the next) and the persistence behavior of `ignoreNumbers` across calls, which enriches understanding beyond the field descriptions.

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 and resource ('Watch any public page for changes') and explains the two-phase token protocol in the first two sentences. An agent immediately understands this is a stateful page-diffing tool, distinct from generic fetch/crawl siblings.

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?

The description lays out the operating protocol clearly: fetch-and-token on the first call, send-token-next-time on subsequent calls, and an option to ignore number-only changes. It does not explicitly compare against the sibling page-changes-summary, so routing between the two is left to inference.

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