n8n_update_variable

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

No annotations are provided, so the description carries the full burden of behavioral disclosure. It merely says 'update an existing variable' and does not explain partial-update semantics, what happens to omitted fields, authentication needs, or return behavior. This is a mutation tool with zero behavioral transparency.

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 sentence with no wasted words, and it is front-loaded with the action. However, it is underspecified for a tool with four parameters, omitting what fields can be updated and how optionality behaves, making it minimally acceptable rather than effective.

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 mutation tool with four parameters and no output schema, this description is insufficient. It does not explain that key/type/value are optional, whether the update is partial or full, or what the tool returns. It lacks enough context for an agent to invoke it confidently.

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?

The schema description coverage is 100%, with each parameter labeled 'opcional' and the required variable_id explained. The description adds no parameter information, but the schema already provides the necessary semantic details, so the baseline of 3 applies.

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 the specific verb 'actualizar' and identifies the resource as 'una variable existente', clearly distinguishing this update operation from sibling tools like create, get, or delete variable. It communicates exactly what the tool does.

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 phrase 'existente' implies the tool is for variables that already exist, but it does not explicitly state when to use it versus alternatives like n8n_create_variable or n8n_delete_variable. There is no when-not-to-use guidance, only a minimal implied context.

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