get_performance_report

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

Annotations already indicate readOnlyHint=true and openWorldHint=true. The description adds that metric names are validated locally, money metrics are in USD, and defaults to last 7 days. No contradictions. Some additional context like rate limits or auth could be beneficial.

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?

The description is concise, well-structured, and front-loaded with purpose. Each sentence adds value: purpose, accepted metrics, defaults, and alternatives. No unnecessary words.

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?

Although the description covers purpose and usage, it lacks details about the response structure since no output schema is provided. It mentions money in USD but doesn't describe the format of the performance totals. This is a gap given the tool's complexity.

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 100%, so baseline is 3. The description adds value by explaining that metric names are friendly and lowercase, giving examples, and noting default behavior. It repeats some schema defaults but provides extra context.

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 clearly states that the tool returns performance totals for an ad account over a date window, distinguishes from siblings like get_daily_performance, compare_periods, and compare_ads, and specifies the resource and verb.

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 explicitly mentions when to use this tool (for totals over a date window) and suggests alternative tools for different needs: get_daily_performance for per-day breakdown, compare_periods for change, compare_ads for ranking ads.

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