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

Annotations already establish read-only, idempotent, non-destructive, open-world behavior, so the bar is lower; the description still adds the meaningful constraint that only static HTML is inspected and that runtime callbacks, activation, consent behavior and Meta receipt are out of scope, plus the connected-site requirement. It does not describe pagination or rate limits, but those are largely irrelevant for a single-page check.

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?

Four short sentences, front-loaded with the core action and scope before the exclusions and prerequisite. Dense with no filler, though the exclusion list could arguably be compressed.

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, so the description carries return-value burden; 'compares them with the connected project' implies a comparison verdict but does not say what the result looks like. For a low-complexity, two-parameter read tool the remaining gap is minor.

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 50% (only 'html' is documented as 'page HTML fetched by the agent'). The description compensates by explaining the two input paths — a public fetch of the URL versus agent-supplied HTML — which gives the otherwise undocumented 'url' parameter clear meaning and clarifies the mutual roles of the pair.

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 (checks) and resource (a page's static HTML) plus exactly what it looks for (Tyton container and Meta Pixel references) and the comparison target (the connected project). It also bounds the scope by declaring it does not verify runtime behavior, which cleanly separates it from runtime-oriented siblings like check_live_setup.

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 the two accepted input modes ('a public fetch or HTML supplied by the agent') and the prerequisite 'Requires a connected site', and rules out the runtime cases via the 'does not verify' sentence. It stops short of naming the sibling tool an agent should use for those runtime cases, so routing is implied rather than explicit.

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