opn_update_firewall_rule

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

No annotations are provided, so the description carries the full burden, and it delivers extensively. It discloses savepoint auto-revert behavior, version-specific differences, the need to confirm changes on older OPNsense, the lack of automatic rollback on 26.7+, and recommends config backup when savepoint support is unavailable. This is rich, actionable behavioral context well beyond the schema.

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 long but necessarily so for a 19-parameter, behaviorally complex tool. It is front-loaded with the core purpose, then usage guidance, then critical version caveats, then the parameter list, then return values. Every section earns its place with no filler or redundancy.

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 19 parameters, no annotations, zero schema-level parameter descriptions, and a mutation-heavy operation, this description is exceptionally complete. It covers invocation, prerequisites, operation scope, safety/rollback behavior, all parameter semantics, and return shape. The output schema exists, so the description appropriately does not need to elaborate return values beyond naming the keys.

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, and it does. Every one of the 19 parameters is listed with concise semantics and value hints (e.g., action: 'pass', 'block', or 'reject'; source_net: source address/network or 'any'; quick: first-match wins vs last-match-wins). This adds meaning the raw schema completely lacks.

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 opens with a specific verb+resource statement: 'Update an existing MVC firewall rule by UUID with savepoint protection where supported.' It clearly distinguishes this from sibling tools like add/delete/toggle/list firewall rules by focusing on modifying existing rules by UUID.

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 gives explicit usage context: 'Use this when you need to modify a firewall rule's action, source/destination, protocol, ports, or other properties.' It also directs agents to call opn_list_firewall_rules first to find the UUID and check opn_mcp_info for savepoint support. It does not explicitly state when not to use it versus alternatives like opn_toggle_firewall_rule, so it falls just short of a 5.

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