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

Annotations already declare readOnlyHint=true, idempotentHint=true and destructiveHint=false, so the safety profile is covered. The description adds one genuinely useful behavioral detail: that only draft workspaces are returned, not published versions, but says nothing about ordering, counts, or pagination.

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 functional content is one tight sentence with the scope up front. The trailing 'Tools revision: 5c9bea8f.' line is metadata noise that adds nothing for an agent.

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 one required parameter, a published output schema, and annotations covering safety, the description supplies everything needed to invoke the tool. Minor gaps are the missing upstream dependency on container discovery and any note on result volume.

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%, so the description must carry the parameter burden, and it does: the single required parameter is shown in its full path form accounts/<a>/containers/<c>. It stops short of saying whether a bare container ID would also work.

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 (list) and resource (draft workspaces of a container), and gives the container path shape accounts/<a>/containers/<c>. The GTM resource naming separates it from siblings like gtm_list_tags or gtm_list_containers, though it doesn't explicitly contrast with them.

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?

No when-to-use guidance, no stated prerequisite that a container ID must first come from gtm_list_containers, and no indication of when a caller would want draft workspaces versus published version headers (gtm_list_version_headers).

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