built_in_variables_revert

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

No annotations are provided, so the description must carry full weight. It identifies the tool as a write operation and mentions required conditions, but does not disclose failure modes, reversibility, or permission requirements beyond the environment variable.

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 two sentences, front-loaded with a '[WRITE]' label, and every word adds value. It is concise with 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?

The tool has 5 required parameters, no output schema, and the description covers only the action and prerequisites. It lacks details on success/failure behavior, side effects, or how to verify the revert. Adequate but not comprehensive.

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 only 20% (only 'type' has a description). The description mentions that 'type' is the built-in variable type and confirms the 'confirm' parameter must be true, but does not clarify the accountId, containerId, or workspaceId parameters.

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 uses a specific verb ('Revert'), identifies the resource ('built-in variable'), and specifies the context ('to the original container version'). It clearly distinguishes from sibling tools like built_in_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 states prerequisites (GTM_MCP_ENABLE_WRITES=true and confirm=true), which guides when to use the tool. However, it does not explicitly mention when not to use it or provide alternative tools for similar tasks.

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