Create a Google Tag Manager tag with predictable JPTB naming, reusing an existing equivalent tag to prevent duplicates.
Create a GTM tag (full tag object). Use predictable JPTB naming; reuse/update an equivalent existing JPTB tag instead of duplicating.
| Name | Required | Description | Default |
|---|---|---|---|
| tag | Yes | ||
| account_id | Yes | ||
| container_id | Yes | ||
| workspace_id | Yes | ||
| connection_id | No | ||
| session_token | No |
Changes observed during successful MCP inspections.
v0.1.1Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations, the description carries the full burden of behavioral disclosure. It describes what the tool does ('Create') and a naming expectation, but does not explain side effects, failure modes, required permissions, whether the tag is inserted immediately, or how to handle existing tags beyond avoiding duplication.
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 short and front-loaded, stating the core action immediately. The second sentence adds a valuable guardrail against duplication. The acronym 'JPTB' is unexplained, which slightly reduces clarity, but overall there is no wasted text.
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?
This is a creation tool with nested object parameters, no output schema, and no annotations, yet the description provides minimal operational context. An agent would not know how to build a valid tag object, what fields are required beyond the four IDs, or what response to expect. The description is too thin for the tool's complexity.
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 input schema has 0% description coverage and the description adds no parameter-level meaning. It mentions 'full tag object' but does not explain account_id, container_id, workspace_id, connection_id, session_token, or the structure of the nested tag object. The agent must rely entirely on field names and external knowledge.
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 clear action and resource: 'Create a GTM tag (full tag object).' It also clarifies that the created tag should follow predictable JPTB naming, which signals the tool is for full object creation rather than partial edits. This distinguishes it from sibling tools like gtm_update_tag.
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 gives explicit guidance to reuse or update an equivalent existing JPTB tag instead of duplicating, which tells the agent when not to create. It does not explicitly name alternatives such as gtm_list_tags or gtm_update_tag, but the intent is clear enough for routing.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.