n8n MCP Server

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

With no annotations provided, the description carries full burden but only states it 'retrieves' executions. It doesn't disclose whether this is a read-only operation, if it requires authentication, rate limits, pagination behavior (despite having a 'limit' parameter), or what the return format looks like. For a tool with 5 parameters and no output schema, this is a significant gap in behavioral context.

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, efficient sentence that front-loads the core purpose ('retrieve all executions') and adds qualifying information ('from your instance with optional filtering'). There's no wasted verbiage or redundant information.

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 5 parameters with 0% schema coverage, no annotations, no output schema, and multiple sibling tools, the description is incomplete. It adequately states what the tool does at a high level but fails to provide necessary context about parameter usage, behavioral expectations, or differentiation from similar tools, making it insufficient for reliable agent use.

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 must compensate but only mentions 'optional filtering' generically. It doesn't explain what 'clientId' represents (required parameter), what 'includeData' controls, the meaning of status enum values, how 'workflowId' filters, or how 'limit' affects results. The description adds minimal value beyond the bare schema.

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 clearly states the verb 'retrieve' and resource 'executions', specifying it retrieves 'all executions from your instance'. It distinguishes from sibling 'get-execution' by indicating it lists multiple executions rather than fetching a single one. However, it doesn't explicitly differentiate from other list tools like 'list-workflows' beyond the resource name.

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 'optional filtering' which implies when to use parameters, but provides no explicit guidance on when to use this tool versus alternatives like 'get-execution' for single executions or other list tools for different resources. No context about prerequisites, exclusions, or comparison to siblings is given.

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