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

Annotations already declare readOnlyHint/destructiveHint=false, so the safety profile is known; the description adds value beyond that with the five-minute token lifetime, the approval-scope confirmation requirement, and the irreversibility of disabled blank conditions. 'IPP' and 'approval-scope confirmation' are used as unexplained jargon, which limits the credit.

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?

Four short sentences, front-loaded with the core purpose, with no filler. The 'Requires approval-scope confirmation' sentence is the weakest because it is too compressed to be actionable.

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 preview/mutation tool with a deep nested schema and no output schema, the description covers the workflow shape (preview, token, no apply) but leaves the agent unsure what the preview contains and what 'approval-scope confirmation' requires in practice, plus the payload fields are unexplained.

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 the single input wraps a nested patch object, so the description must compensate. Saying 'sparse change' usefully conveys PATCH semantics (only supplied fields change, nulls mean untouched), but it never mentions rule_id, actions, priority, or is_active, leaving most of the payload undocumented.

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 action (prepare a sparse change) against a specific resource (an exact rule), and the final clause 'it does not apply the change' makes the preview-vs-apply distinction explicit. It never names update_automation_rule as the sibling that actually applies it, but the read-only framing 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?

Gives real usage boundaries: existing blank conditions cannot be re-enabled, and export/notification rules can only be paused here while enabling/editing them requires IPP. What is missing is the follow-through instruction naming the tool that consumes the returned confirmation token.

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