list_failed_services

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

No annotations are provided, so the description carries full burden. It states it lists failed units, but does not disclose whether it requires permissions, affects system state, or how the scope parameter (default 'system') influences behavior. No mention of output format, ordering, or any side effects.

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: one phrase delivers the core purpose. No wasted words, and the most important information ('All failed units') is front-loaded.

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?

Despite having an output schema, the description omits critical context about the single parameter (scope) and behavioral details. For a tool with only one parameter, this is a significant gap. The description does not fully cover what the agent needs to invoke it correctly.

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?

There is one parameter 'scope' with 0% schema description coverage. The tool description does not mention the parameter at all, failing to add any meaning beyond the schema's basic type and default value.

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 lists all failed units and positions it as the fastest 'what's broken?' check. It uses a specific verb and resource ('All failed units'), and effectively distinguishes itself from sibling tools like 'list_services' by focusing exclusively on failed state.

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 use for quickly checking broken components, but provides no explicit guidance on when not to use this tool or alternative tools like 'list_services', 'query_journalctl', or 'diagnose_crash'. The context is clear but lacks comparative usage direction.

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