n8n: Set variables

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

The description adds useful context beyond the annotations: it is a bulk operation and requires an Enterprise/Pro license. The annotations already disclose destructiveHint=true, so the agent knows this is a dangerous write. However, the description does not explain what happens to existing variables, whether missing variables are created, or whether partial failures are possible.

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-loads the key facts: unified/enterprise tags, bulk behavior, and license requirement. The tags are somewhat noisy, but there is no rambling or filler. It is efficient overall.

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 bulk mutation with a required site parameter and an untyped nested variables object, the description is incomplete. It omits how 'site' scopes the operation, what format 'variables' expects, and whether the operation is atomic. No output schema exists, so the description should do more to describe behavior.

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%, so the description carries the full burden for explaining parameters. It only hints that the 'variables' parameter is a bulk collection; it says nothing about the required 'site' parameter or the expected shape of the nested variables object. This is inadequate for a two-parameter tool with a nested object.

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: 'Bulk set multiple variables at once.' This distinguishes it from single-variable siblings like n8n_create_variable and n8n_delete_variable. However, it does not clarify whether 'set' means upsert, overwrite, or create-only, which leaves an important semantic gap.

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 when to use it by saying 'Bulk set multiple variables at once,' which signals batch operations. It also states the Enterprise/Pro license requirement. But it gives no explicit guidance on when to use this versus n8n_create_variable or other variable tools, and no exclusions are mentioned.

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