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

Annotations already cover the safety profile (readOnly, non-destructive, closed-world), and the description adds genuinely new behavioral context: reports are dated, missing hosts return found:false, and the tool 'never guesses a nearest match'. That no-fuzzy-fallback guarantee is exactly the kind of trait an agent cannot infer from annotations.

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?

Purpose is front-loaded and the closing instruction ('Cite the report URL and its date') is actionable rather than filler. The middle enumerations make the first sentence long and slightly run-on, but every clause carries information.

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 must convey the return shape, and it does: tested capabilities, pass/fail, probe time, apparent agent affordances, and discovery source, plus the found:false edge case. Auth requirements and any rate limits remain unstated, a minor gap for a read-only lookup.

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% and the single host parameter is already documented with an example ('example.com'), so the schema does the heavy lifting. The description only restates that the target is one listed website/host, adding no format or resolution detail beyond 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?

States a specific verb and resource ('Fetch Known Good's dated verification report for one listed website') and enumerates the report's contents, so the agent knows exactly what comes back. The scope ('one listed website', 'this specific host') separates it from the broader lookup siblings check_webmcp and find_capability.

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 clear use case in the form of the question it answers ('is this specific host agent-ready?'), which tells the agent when to reach for it. It does not explicitly name check_webmcp or find_capability or state when not to use it, so it falls short of full routing guidance.

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