built_in_variables_list

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

With no annotations, the description must disclose behavioral traits. It states it's a list (read) operation but does not mention auth requirements, rate limits, pagination beyond schema, or side effects. The description adds minimal transparency beyond the obvious.

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?

A single, well-structured sentence that concisely communicates the tool's purpose without extraneous information.

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?

For a simple listing tool, the description covers the basic purpose but lacks details on return format and pagination behavior. Without an output schema, the description should at least hint at the structure of results. It is minimally complete but not thorough.

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 40% (only maxPages and pageToken have descriptions). The tool description does not explain any parameters or add meaning beyond the schema. For a tool with three required parameters (accountId, containerId, workspaceId), the description offers no guidance on their purpose or values.

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 clearly states the action (list), the resource (built-in variables), and the context (enabled, in a GTM workspace), distinguishing it from sibling tools like variables_list or built_in_variables_enable.

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 for listing enabled built-in variables but does not explicitly guide when to use this tool versus alternatives like variables_list or built_in_variables_enable. No when-not-to-use or prerequisite information.

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