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

Annotations already disclose destructiveHint=true, idempotentHint=true, openWorldHint=true, and readOnlyHint=false, so the "[write]" tag is largely redundant. The "and/or" phrasing usefully signals a partial update, but the description does not say what the destruction entails, whether omitted parameters are left untouched or reset to null, or whether re-editing is safe to retry.

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?

A single sentence with the write marker, the resource, the identifier options, and the mutable fields front-loaded. Nothing is padded, though the trailing parenthetical packs several facts into a dense clause that takes a moment to parse.

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 four-parameter mutation tool with no output schema, the definition covers identity resolution and the two editable attributes, which is the core of what an agent needs. The remaining gap is partial-update semantics — with zero required parameters it is unclear whether omitting the threshold leaves it unchanged or clears it, which matters for a destructive write.

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 coverage is 0%, so the description carries real weight here: it establishes that ads_rule_id and ads_rule_uuid are alternative identifiers and that ads_rule_status accepts ACTIVE or PASSIVE — none of which the schema states (no descriptions, no enum). However, ads_rule_threshold is named but never explained (unit, scale, direction of the comparison), leaving one of four parameters semantically empty.

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?

"Change an ad monitoring rule" names a specific verb and resource, and the parenthetical enumerates the two mutable facets (threshold, status). It is clearly distinguishable from create_ads_rule, delete_ads_rule, and list_ads_rules, though it never names a sibling 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 implied by the verb and by the listed mutable fields: use this to alter an existing rule rather than to create or remove one. There is no explicit when/when-not guidance, no prerequisite statement (e.g. that the rule must already exist), and no alternative named.

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