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

Annotations already declare readOnlyHint=true, idempotentHint=true, destructiveHint=false and openWorldHint=false, so the safety profile is fully covered structurally. The description adds only the hierarchical location of containers under an account; it says nothing about pagination, result volume, or ordering, which is the behavior a listing agent would still want.

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 first sentence is front-loaded and waste-free. The trailing "Tools revision: d80f65c0." is build metadata that adds nothing for an agent deciding whether and how to call the tool.

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 an output schema present, return values need not be described, and annotations cover the safety profile. For a one-parameter listing tool the description is close to sufficient, but it leaves the account-id format ambiguity and any paging caveat unaddressed.

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 the single "account" parameter, so the schema carries no meaning on its own. The description partially compensates by showing the expected resource-name form "accounts/<id>", but does not say whether a bare numeric id is also accepted or how accounts are discovered.

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?

The description gives a specific verb and resource ("List containers") scoped to a GTM account, so an agent can tell it apart from gtm_list_accounts or gtm_list_workspaces by the resource level. It does not explicitly name those siblings as alternatives, keeping it below a 5.

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 only implied: the "(accounts/<id>)" path hints that an account id is a prerequisite, presumably obtained from gtm_list_accounts, but there is no explicit when-to-use or when-not guidance. No alternatives or exclusions are stated.

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