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

Annotations already declare readOnlyHint=false, idempotentHint=true, and destructiveHint=false, so the safety profile is covered. The description adds a genuinely non-annotated behavioral fact: the fault's history remains on the timeline, confirming that removal is a disarm rather than a destructive delete. It still says nothing about permissions, error cases, or whether the fault can be re-armed.

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?

Two short sentences with zero filler, and the core effect is front-loaded before the history-retention detail. Every clause earns its place.

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 simple two-parameter mutation with no output schema, the description covers purpose and the key post-condition (history preserved). However, with 0% parameter coverage it should do more to explain run_id/fault_id scope, and it omits any note on failure or repeat-call behavior.

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% and neither of the two required parameters (run_id, fault_id) is mentioned in the description, so no meaning is added beyond the bare property names. The description leaves the agent to infer how a fault is identified and in what scope.

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?

"Disarm a fault so it fires no more" gives a specific verb plus resource and states the operational effect, making it clearly distinct from the sibling rig.fault.add. It does not, however, name that sibling or any other tool to differentiate against explicitly.

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?

Usage is only implied by the effect clause: an agent can infer you disarm a fault when it should stop firing, and the counterpart rig.fault.add exists in the sibling list. There is no explicit when-to-use statement, no exclusions, and no mention of prerequisites such as the run needing to be active.

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