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

Annotations already declare readOnlyHint, idempotentHint, destructiveHint=false and openWorldHint=false, so the safety profile is fully covered. The description adds only a conceptual gloss on what auto rules are and nothing behavioral — no pagination behavior, no ordering, no scope (all rules vs. workspace rules) beyond what annotations already imply.

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?

It is a single short sentence with no padding, so there is nothing to trim — but brevity here comes from under-specification rather than tight writing, and the parenthetical domain gloss is the only content-bearing element.

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 list tool with three optional filtering/pagination parameters and no output schema, an agent still lacks return-shape expectations (fields per rule, total counts, ordering), scope of the listing, and how to move through pages. The parenthetical definition of auto rules is not enough to call this correctly with confidence.

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 100%, with page, search, and per_page each documented (defaults, max 100). The description adds no filtering or pagination semantics beyond the schema, so the baseline 3 applies.

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 is a noun phrase rather than a verb-resource statement: "The auto-rule library (auto-rule... )". It does clarify what an auto rule is (scheduled campaign-optimization), which helps the agent understand the domain, but it never explicitly says this tool lists/returns them, leaving the action to be inferred from the name.

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?

No when-to-use guidance and no mention of alternatives. Siblings such as get_auto_rule (single rule), list_auto_rule_runs (executions), and create_auto_rule/attach_auto_rule are never referenced, so the agent must infer that this is the paginated index rather than a detail or run-history endpoint.

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