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

With no annotations, the description carries the full burden and does substantial work: it discloses state scoping ("under your key"), authentication (Bearer token in Authorization), and cost (€0.002 per check). It also reveals that js defaults to true, meaning Chromium rendering is the slow/expensive default. Gaps remain on rate limits, what 'delete' destroys, and pagination for 'list'.

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?

The change-detection behavior, cost/auth model, and parameter glossary are packed into three sentences with no filler, and the core behavior plus return shape are front-loaded before the parameter list.

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 spelled out, yet the description still summarizes them helpfully. Cost and auth context are covered; the only shortfall is that 'list' and 'delete' operation semantics are named but not described, leaving an agent unsure what those modes do or require.

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 it does: all four parameters are explained with defaults, and op is given an inline enumeration (check default | list | delete) that the schema lacks entirely. One inconsistency: the description calls js a bool while the schema types it as string.

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 uses a concrete verb and resource: it snapshots a page's main text and reports change status, added/removed lines, and similarity. That is clearly distinct from siblings like screenshot, browser, or text_diff, though it never names those siblings to reinforce the distinction.

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?

"Schedule calls from your side" is a genuine usage hint, making clear the tool is stateless-triggered and the caller owns the polling cadence, and the op values imply three usage modes. However, it never states when to prefer this over alternatives such as text_diff or url_to_markdown, nor what prerequisites exist for 'list' and 'delete'.

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