List systemd services on a host, optionally filtered by running, failed, or all states. Use it to inspect service status across servers from the safety-gated opsgate MCP server.
List systemd services on a host, optionally filtered to running or failed units.
| Name | Required | Description | Default |
|---|---|---|---|
| host | No | target host name from the opsgate config; omit for the default host | |
| state | No | filter by state: running, failed, or all (default running) |
Changes observed during successful MCP inspections.
v0.1.2Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations, the description carries the full behavioral burden. 'List' reasonably implies a read-only, non-destructive operation, which is the key trait, but nothing is said about permissions/auth needs, output volume, or pagination. It conveys the safety profile implicitly rather than explicitly.
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?
A single tight sentence with the resource front-loaded and the optional filter appended. Nothing is wasted and there is no filler.
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?
For a low-complexity read tool with two fully documented parameters and no output schema, the description covers the essentials. Minor gaps: it doesn't note the default state or the 'all' value the schema supports, and with no output schema an agent gets no hint of what a listing returns.
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 coverage is 100%, so both parameters (host and state) are already fully documented in the schema, including the default host and the state default of running. The description adds only the 'running or failed' filter framing and actually omits the 'all' option the schema lists, so it adds no meaningful semantics beyond the 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?
States a specific verb (List) and resource (systemd services on a host), immediately distinguishing it from mutation siblings like service_restart or service_stop. It does not explicitly name service_status as the single-unit alternative, but the list scope is unambiguous.
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 describes the filter capability but gives no when-to-use guidance: it never says to reach for this over service_status for a single unit, nor when each filter state is appropriate. Usage is only implied by the tool name and verb.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.