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

No annotations are supplied, so the description carries the full burden, and it discloses almost nothing. It never says whether the check is a slow external fetch (PageSpeed runs typically take tens of seconds), whether it needs an API key, how results are returned, or what happens on an unreachable URL. Claiming it runs "the same code the tool page runs" vaguely implies parity with a web UI but gives no actionable behavioral context.

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 description is short, but every sentence is filler: the first restates the name, the second is an unexplained implementation remark, and the third is a canned scope label. None of them is front-loaded with actionable information, so brevity here reflects under-specification rather than economy.

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 annotations, no output schema, and a network-dependent check, the description needs to explain result shape and cost. It explains neither, and the strategy parameter (desktop vs mobile) is left ambiguous, so an agent cannot confidently call this or interpret the result.

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% for both parameters, so the schema already documents them and the baseline is 3. The description adds nothing about the url or strategy parameters, and notably does not clarify the valid values for strategy (the schema describes it only as "Optional." with no enum), which is a missed opportunity rather than a schema-driven gap.

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?

"PageSpeed" merely restates the tool name, and "Runs the same code the tool page runs" is a vague implementation note rather than a statement of what the tool measures. "Scope: check" is boilerplate that does nothing to distinguish it from the many sibling checks (check_speed, check_performance, check_ai_check). An agent cannot tell from the text whether this returns Lighthouse scores, Core Web Vitals, or something else.

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?

There is no when-to-use guidance, no prerequisites, and no mention of the obvious alternatives check_speed or check_performance, which likely overlap. The only usage signal is the word "check" in the scope line, which the agent could already infer from the name.

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