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

Annotations already declare readOnlyHint, idempotentHint and destructiveHint=false, so safety is covered. The description adds real content context: the returned steps differ per platform, and the shopify variant includes a custom pixel that counts product views, carts, checkouts and purchases with revenue — useful to know before promising the agent a plain snippet. It omits any auth/permission or prerequisite notes.

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?

A single front-loaded sentence whose fragments each carry information; the platform enumeration and the closing 'Free.' both earn their place with no filler.

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?

For a read-only lookup with rich annotations and no output schema, the description covers what comes back and which platform variants exist. It does not cover the prerequisite relationship with analytics_add_site/list_sites, which is the one thing an agent needs to sequence the install workflow correctly.

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 only 50%: site is documented in the schema, platform is a bare enum. The description compensates by narrating the platform values — html works on any site, shopify means the theme plus a custom pixel, plus wordpress, webflow, google_tag_manager — which helps the agent pick the right value. It adds nothing about the required site parameter or its domain-vs-site_id forms.

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 outcome: step-by-step instructions for placing the counting script on a site, enumerated per platform. It is not confused with the data-returning siblings (analytics_stats, analytics_funnel), though it never names those siblings or analytics_add_site to make the distinction explicit.

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: the platform list tells the agent this is the install-onboarding path, and no when-not or alternative is given. Nothing says whether the site must already be registered (via analytics_add_site) before calling, which is the main decision point.

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