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

Annotations already declare readOnlyHint=true and openWorldHint=true, so the safety profile is covered. The description adds the useful detail that the result pairs metadata with the published live version and its counts. It does not mention auth requirements or what happens with multiple workspaces beyond the optionality note.

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?

Two short sentences with no filler; the resource/payload is stated first and the parameter note second. Reasonably front-loaded, though it reads as a label plus a param gloss rather than a cohesive explanation.

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?

An output schema exists, so return values needn't be documented, and the sole optional parameter is explained. For a one-param read-only info tool this is largely sufficient; only sibling differentiation is missing.

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%, so the description carries the burden, and it does explain the single parameter: workspace is the customer workspace slug and is optional when only one workspace exists. That is meaningful semantic detail the bare schema lacks.

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 states it returns GTM container metadata plus the currently published live version (with tag/trigger/variable counts), which is more than a title restatement. However, it never says which container it refers to (the schema exposes no container ID) and it does not distinguish itself from siblings like gtm_list_containers or gtm_get_version.

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 indication of when to use this versus the many related GTM tools (gtm_list_containers, gtm_get_version, gtm_workspace_status). The only usage hint is the parenthetical that workspace is optional when there is a single workspace, which is about a parameter, not tool selection.

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