n8n: Delete variable

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

Annotations already declare destructiveHint=true, readOnlyHint=false and idempotentHint=false, so the safety profile is largely covered. The description adds the license prerequisite, which annotations cannot express, but says nothing about whether the key is permanently removed, what happens if the key does not exist, or whether a failed delete is retryable despite idempotentHint=false.

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?

Very short and front-loaded, with the action stated first and the eligibility constraint second. The bracketed tags "[UNIFIED]" and "[Enterprise]" add little for an agent, but the sentence structure itself is efficient with no wasted clauses.

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 destructive two-parameter tool with no output schema and zero schema documentation, the description is too thin: it never defines `site`, never states the outcome of a successful or failed delete, and offers no confirmation guidance. The license note is helpful but does not compensate for the undocumented required parameter on an irreversible operation.

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 0% for two required parameters, so the description must carry the burden and it does not. "Environment variable" loosely implies what `key` means, but the `site` parameter is never mentioned or explained anywhere, leaving an agent to guess whether it is a tenant, instance URL, or hostname.

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 and resource ("Delete an environment variable"), which cleanly separates it from the create/get/update_variable siblings and from the many other delete_* tools. The scope is unambiguous, though it does not explicitly name which sibling to use instead when the intent is a read or update.

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 supplies one real usage constraint — an Enterprise/Pro license is required — which is genuinely actionable. It gives no guidance on when to choose this over n8n_update_variable (e.g. clearing a value vs removing the variable) or any caution about confirming before permanent removal, so usage is only implied.

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