n8n-mcp

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

With no annotations provided, the description carries full burden for behavioral disclosure. It mentions the 'write_mode' requirement which hints at permission needs, but doesn't describe what 'update' entails (e.g., whether it overwrites or merges, what happens to unspecified fields, if changes are reversible, or any rate limits). For a mutation tool with zero annotation coverage, this leaves significant behavioral gaps.

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 brief (two short sentences) and front-loaded with the core purpose. It wastes no words, though the second sentence about 'write_mode' could be more integrated. The structure is efficient, though slightly fragmented between the two statements.

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?

Given this is a mutation tool with 5 parameters, 0% schema description coverage, no annotations, but with an output schema, the description is insufficient. It doesn't explain what fields can be updated, how the update behaves, what the output contains, or how it differs from sibling tools. The presence of an output schema helps but doesn't compensate for the missing behavioral and parameter context.

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%, meaning none of the 5 parameters have descriptions in the schema. The tool description provides no information about what parameters are available, what they mean, or how they should be used. This leaves all parameters completely undocumented, failing to compensate for the schema coverage gap.

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 the verb 'update' and resource 'existing workflow', which clarifies the basic purpose. However, it doesn't differentiate this tool from sibling tools like 'update_workflow_tags' or 'create_workflow', leaving the scope somewhat vague. The mention of 'write_mode' requirement adds specificity but doesn't fully distinguish it from other workflow modification tools.

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 mentions 'Requires write_mode' which provides a prerequisite condition, but it doesn't offer guidance on when to use this tool versus alternatives like 'create_workflow' or 'update_workflow_tags'. No explicit when/when-not scenarios or sibling tool comparisons are provided, leaving usage context incomplete.

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