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

Without any annotations, the description fully discloses key behaviors: net calculations after a ~10% fee, gross credits, platform fee, cashout fields, USD peg, analytics warehouse lag (~15m), and publisher_id scoping. This gives the agent a strong understanding of the tool's operational traits.

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 information-dense but well-organized into three sentences, front-loading the core purpose. It covers the main output fields and operational details without excessive verbosity, though the middle sentence is a long list that could be slightly restructured for readability.

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 no output schema, the description comprehensively outlines expected return data (itemized totals, daily series, money fields) and limitations (lag, scope), covering all period modes and cost breakdowns. This is complete enough for an agent to understand the report's content and invoke it properly.

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 descriptions already cover 100% of parameters, including formats and defaults. The description adds minimal extra parameter meaning beyond reiterating period modes and specifying UTC, which is already implied by the date formats. Thus it meets the baseline but does not significantly enhance schema semantics.

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?

Purpose is explicitly stated: 'See what you earned for any day, week, month, or custom range' with period options clearly enumerated. It distinguishes from sibling publisher reports by emphasizing general scope ('Scoped to your publisher_id') versus per-campaign/per-placement variants.

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 clear context for when to use this tool (publisher earnings, various time periods) but does not explicitly mention alternatives or exclusions like get_publisher_report_by_campaign or by_placement. Usage is implied rather than directly contrasted with siblings.

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