control_service

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

The annotations already indicate the tool is mutating (readOnlyHint=false, destructiveHint=false). The description adds meaningful context by warning that stopping critical services (dhcpd, unbound, sshd) will disrupt network operations, which is not conveyed by the annotations. It does not discuss permission requirements, but the specific safety warning adds value beyond the structured data.

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 concise, consisting of two sentences: one for the tool's purpose and one for a critical safety warning. The warning is not boilerplate; it names specific services and the consequence of stopping them, earning its place. No unnecessary repetition of schema details.

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 simple two-parameter schema, clear annotations, and presence of an output schema, the description sufficiently covers the tool's behavior. It states the operation, the target resource, and the key risk (disruption of network operations). There are no significant gaps for this level of complexity.

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 input schema already documents both parameters with descriptions and examples (service_name, action). The description's warning adds an extra service example ('sshd') but otherwise does not elaborate on parameter semantics. With 100% schema description coverage, the description contributes little beyond the schema, meriting the baseline score of 3.

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 tool's function: 'Start, stop, or restart a service on the live pfSense appliance.' This provides a specific verb (start/stop/restart), resource (service), and scope (live appliance), clearly distinguishing it from read-only sibling tools like search_services.

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 implies the tool is used when you need to change a service's state but does not explicitly contrast it with alternative tools such as search_services for listing services. The warning about critical services gives cautionary context but no explicit guidance on when not to use the tool. Thus usage is implied rather than explicitly delineated.

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