Get channel breakdown (Organic, Paid, Direct, etc.)

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

Annotations already declare readOnlyHint, idempotentHint, and destructiveHint, so the safety profile is clear. The description adds that the response includes a monthly timeseries and an aggregated roll-up, which provides useful behavioral context beyond annotations.

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?

Three sentences effectively convey the output, use cases, and response structure. Every sentence adds value, with no redundancy or fluff.

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?

Given the rich annotations (readOnly, idempotent) and the detailed explanation of the response structure (monthly timeseries + roll-up), the description is largely complete for a read-only aggregate report. No output schema exists but the description covers the important aspects.

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%, so every parameter is already documented. The description does not add significant new meaning for parameters beyond what the schema provides, meeting the baseline for high coverage.

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 explicitly states the tool returns revenue, sessions, transactions, CR, and AOV broken out by marketing channel for one or more domains, listing specific channels. It also provides use cases, clearly distinguishing it from sibling tools like grips_get_devices or grips_get_daily_performance.

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?

The description advises when to use the tool (understand channel mix, evaluate paid-vs-organic balance, spot channel shift) but does not explicitly mention when not to use it or provide alternatives among siblings. This is clear context for use, but lacks explicit exclusions.

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