n8n_list_variables

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

The readOnlyHint annotation already signals that this is a safe read, and the description merely restates 'List' without adding behavioral nuance. It does not disclose whether filters are optional, whether results are paginated, whether variable values are masked, or how project scoping affects the returned set.

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 a single front-loaded sentence with zero filler. It states the action and the resource directly and efficiently.

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 list operation with two optional filters and a read-only annotation, the description is minimally viable. However, it lacks clarity about how filters interact with 'all', whether project scope is required for viewing variables, and what the return payload contains, especially since no output schema is provided.

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 100%, with both 'state' and 'projectId' described as filters. The description adds no parameter-level meaning beyond what the schema already provides, so the baseline of 3 is appropriate.

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 ('List') and a concrete resource ('all environment variables'), making the tool's purpose immediately clear. While it does not reference sibling tools, there is no competing 'list variables' option among the siblings; the variable CRUD siblings are clearly different operations.

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 usage is implied: this is the tool to call when you need to retrieve environment variables. However, the description does not explicitly state when not to use it or mention alternatives for variable creation, updates, or deletion, leaving the routing to inference.

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