failed_units_tool

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

No annotations are provided, so the description carries the behavioral disclosure burden. 'List' communicates a read-only query, and the return note specifies exactly what the agent gets: a list of failed units with a count. It does not mention side effects, but none are implied for a listing 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 compact: one purpose sentence plus a short Returns block. Every element adds value, and the key scoping detail is front-loaded. There is no filler or repetition.

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 parameterless, read-only listing tool with an output schema, the description is complete. It names the resource, the filtering state, the operational trigger, and the return contents. An agent has everything it needs to select and invoke this tool 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?

The tool has zero parameters, so the schema provides no parameter descriptions and none are needed. The description does not invent parameters or add irrelevant input guidance. Baseline 4 is appropriate for a parameterless tool.

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 states a specific action and resource: 'List units currently in the failed state.' It clearly distinguishes this from sibling tools like unit_list_tool by scoping to failed units, and the 2AM note reinforces its narrow diagnostic purpose.

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 phrase 'first thing to check at 2AM' gives clear operational context for when this tool is appropriate: during quick incident triage. It does not explicitly name alternatives or say when not to use it, though the failed-state scoping implies it is the filtered counterpart to unit_list_tool.

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