List environments

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

Annotations already declare readOnlyHint=true, idempotentHint=true and destructiveHint=false, so safety is covered. The description adds a non-obvious behavioral fact — that preview auth codes are never returned — which matters for anyone expecting full environment objects. It stops short of saying whether all environments are returned or how ordering works.

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?

Three short sentences, front-loaded with what is returned before the identifier formats. Dense and waste-free, though the opening is a fragment without a verb, which slightly weakens the lead.

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?

A read-only single-parameter list tool with an output schema, so return structure needn't be described. Purpose, identifier formats and the auth-code redaction are all covered; only the absence of routing guidance against sibling version tools is a real gap.

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 0% on the single required 'container' parameter, so the description must compensate and largely does: it lists accepted forms (GTM-XXXXXXX, linked G-/AW- destination id, or API path accounts/<a>/containers/<c>). It leaves unstated whether path-form IDs behave identically to public IDs, so it is thorough but not exhaustive.

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 names the resource (environments) and specifies that each entry is paired with the version it serves, so an agent knows exactly what a call returns. It lacks an explicit verb, but 'List' is unambiguous from the name/title and there is no sibling environment tool to confuse it with.

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 statement of when to call this versus alternatives (e.g., gtm_get_live_version or gtm_list_versions) or what prerequisites apply. The only guidance present concerns identifier formats, which is parameter-level rather than usage-level.

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