GTM: Install code

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

Annotations already declare readOnlyHint and openWorldHint, so safety is covered. The description adds the useful detail that the return splits into a head snippet and a noscript body part, but says nothing about permissions, container state requirements, or error behavior for a live container.

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: what is returned first, then the payload breakdown, then usage contexts. No filler and nothing buried.

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 simple read-only tool with no output schema, the description does the important work of describing the return shape. However, with two required identifiers at 0% schema coverage, an agent still has to guess where accountId and containerId come from.

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 0% for two required parameters. The phrase 'of a container' loosely implies containerId, but accountId is never mentioned and neither parameter's format or source is explained, so the description fails to compensate for the schema 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?

States a specific verb and resource — returns the GTM install code of a container — and specifies exactly what the payload contains (head snippet plus noscript body part). That is distinguishable from siblings like gtm_export_container or gtm_list_containers without opening any schema.

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 concrete usage contexts (onboarding, verifying installation on the website), which tells the agent when this is the right tool. It does not name an alternative or state exclusions, so it falls short of a 5.

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