get_performance_report

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

The description discloses key behaviors beyond readOnlyHint: auto-chunking for periods >92 days, sum mode recalculating ratios, and enumeration logic. These add rich behavioral context without contradicting annotations, fully informing the agent of side effects and constraints.

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 (5 sentences) and front-loaded with the core purpose, then progressively adds details on behavior and alternatives. Every sentence earns its place with no redundancy or filler.

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 complexity (9 parameters, output schema exists), the description covers auto-chunking, sum mode, alternative tool recommendation, and response narrowing advice. It provides sufficient context for correct invocation without being excessive, fully leveraging the existing schema and annotations.

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?

With 100% schema description coverage, the description adds value by explaining the sum mode vs daily distinction (related to the 'daily' parameter) and the purpose of metrics/annotate. While the schema already documents all parameters, the description provides operational context that helps the agent understand parameter interplay.

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 defines the tool as a period performance report with named entities, specifying it enumerates level entities, queries /stats, and returns with names attached. It distinguishes itself from siblings like get_campaign_performance and get_stats by mentioning auto-chunking and sum mode, and explicitly recommends low-level StatReports for large scale.

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 provides explicit guidance on when to use this tool (period performance reports) and when not to ('대량' large scale all-account keywords/long history recommends StatReports tool). It also advises narrowing fields via metrics/annotate to reduce costs, offering clear context for optimal usage.

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