gtm_create_container

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

No annotations are provided, so the description carries the full burden. It clearly flags mutation, dry-run by default, refusal on duplicate names, and the fact that nothing is published. These are meaningful behavioral disclosures beyond the schema. It does not cover all possible side effects, but it gives an agent enough to safely invoke the tool.

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 description is a single, front-loaded sentence with a clear warning prefix and no filler. It packs the mutating nature, the action, the return value, duplicate handling, publish behavior, and dry-run default into a compact, immediately scannable format.

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?

Given no output schema and no annotations, the description plus the schema covers the essential details: dry-run default, confirmation requirement, duplicate refusal, no publishing, and the returned id. The missing explicit instruction to obtain the account id via gtm_list_containers is partially covered by the schema, so the overall context is sufficient but not exhaustive.

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?

The schema already documents confirmed and gtm_account_id, while container_name has no schema description. The tool description loosely implies container_name refers to a web container, but it does not add meaningful parameter-level detail. With 67% schema coverage, the description partially compensates but does not fully clarify the unspecified parameter.

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 a specific verb and resource: 'Create a web container in an existing GTM account.' It also specifies the return value (GTM-XXXX id) and a key behavior (refuses on duplicate name). This clearly distinguishes it from sibling tools like gtm_list_containers and platform-specific create tools.

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?

The description implies usage context by saying 'existing GTM account' and the schema notes gtm_account_id comes from gtm_list_containers. However, the description itself does not explicitly state when to use this tool versus alternatives, such as wc_create_account or ga4_create_property, nor does it mention exclusions.

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