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

Annotations already declare readOnly=false, destructive=false, idempotent=false, openWorld=true, so the safety profile is covered. The description adds genuine context beyond that: alerting semantics (email on two consecutive failures and on recovery) and the hard limitation that no form submissions or request bodies are ever sent. It does not mention plan/permission requirements or that a schedule exists with no corresponding parameter.

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?

Front-loads what is monitored and how, then layers optional assertions, then alerting, then the negative constraint. Every sentence carries information; the only mild waste is the brand-name sentence 'Wardzo never submits forms or sends request bodies', which is nonetheless a useful capability boundary.

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?

There is no output schema, and the description never says what is returned (e.g., an endpoint id needed later for remove_endpoint or recheck_site). It also mentions 'on a schedule' without noting that no scheduling parameter is exposed. Adequate for calling the tool, but incomplete for the follow-on workflow an agent will need.

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 100%, so every parameter is already documented, including the GET-only qualifier on expect_keyword and the default of any 2xx/3xx. The description paraphrases those same concepts at a high level without adding syntax or interaction detail beyond the schema, so the baseline of 3 applies.

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 scope: monitoring a URL on one of your sites via GET/HEAD on a schedule, which implicitly distinguishes it from add_site (creates the site) and list_endpoints (read). The description describes the behavior of the thing being created rather than saying plainly 'creates a new endpoint check', so the verb is inferred from the name rather than restated.

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?

Usage is implied rather than stated: 'on one of your sites' signals a site must already exist, and 'Wardzo never submits forms or sends request bodies' sets a real boundary (no POST/form monitoring). There is no explicit when-to-use vs. when-not against siblings such as add_site or recheck_site.

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