OPNSense MCP Server

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

No annotations are provided, so the description carries full burden. 'Delete a VLAN' implies a destructive mutation, but it doesn't disclose behavioral traits such as required permissions, whether deletion is reversible, impact on network connectivity, or error handling (e.g., if VLAN doesn't exist). This leaves critical gaps for safe agent operation.

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 extremely concise with a single sentence ('Delete a VLAN'), front-loaded and zero waste. It efficiently conveys the core action without unnecessary words, though this conciseness comes at the cost of completeness.

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 the tool's destructive nature, no annotations, and no output schema, the description is incomplete. It lacks context on safety, prerequisites, outcomes, or error conditions. For a mutation tool with potential network impact, more guidance is needed to ensure correct agent usage.

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 one parameter ('tag') clearly documented in the schema. The description adds no parameter semantics beyond what the schema provides (e.g., no context on tag format or validation). Baseline score of 3 is appropriate as the schema does the heavy lifting.

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 'Delete a VLAN' clearly states the action (delete) and resource (VLAN), but it's overly basic and doesn't differentiate from sibling tools like 'delete_firewall_rule' or 'haproxy_backend_delete' beyond the resource name. It lacks specificity about what deletion entails (e.g., removing network configuration).

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?

No guidance is provided on when to use this tool versus alternatives. It doesn't mention prerequisites (e.g., VLAN must exist), consequences (e.g., devices on VLAN may be affected), or related tools like 'list_vlans' for checking availability or 'create_vlan' for reversal. The description offers only the bare action.

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