Insights pacing

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

Annotations already declare readOnlyHint=true, idempotentHint=true, destructiveHint=false and openWorldHint=true, so the safety profile needs no restating. The description does add genuine behavioral context beyond that: the metric is modeled/projected to month end rather than raw historical actuals, and the output classifies campaigns as over- or under-pacing. It stops short of stating the account scope, data freshness, or whether spend comes from a specific network.

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 compact clause with zero filler, and the core metric is front-loaded. It is arguably over-compressed, since the fragmentary grammar leaves the action verb and return shape unstated.

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?

An output schema exists, so return values need no explanation, and the tool is a simple one-parameter read. However, for an insights tool whose value depends on timeframe and account scoping assumptions, the description leaves the parameter meaning and selection criteria unaddressed, making it only minimally complete.

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% for the single required parameter customer_id, so the schema contributes only the name and string type. The description adds nothing about which identifier namespace this is (Google Ads customer ID vs. other account IDs) or format expectations. With one trivially-typed parameter this is a modest gap rather than a blocking one.

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 names a concrete analytical output: month-to-date spend compared against daily budgets, projected to month end, surfacing over/under-pacing campaigns. That is specific enough to distinguish it from siblings like insights.anomalies or insights.search_terms. It is written as a noun phrase with no verb ('returns', 'computes'), so it reads like a data dictionary entry rather than an action statement.

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?

There is no explicit when-to-use or when-not-to-use guidance, and no named alternative among the insights.* siblings. The only implicit signal is that the tool is about pacing, which an agent must infer selects it for budget-pacing questions rather than anomaly or search-term analysis.

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