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

Beyond the readOnlyHint=true and destructiveHint=false annotations, the description discloses important behavior: the report is deterministic, composed from a fixed semantic layer with no raw SQL, tied to the ledger, and accrued uses the same earned formula as the money path. It also states the required connected account and that it returns grouped rows plus a total.

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 front-loaded with the core action and key parameter meanings, and most sentences carry useful information. It is somewhat dense and uses emphasis-heavy formatting, but it is not padded with irrelevant material.

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?

For a tool with no output schema, it explains the return shape at a high level: grouped rows plus total. It also covers determinism, read-only behavior, semantic-layer constraints, and authentication. Remaining gaps are minor, such as ordering, pagination, or the exact composition of the total.

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 the schema already documents all four parameters and both enums. The description reinforces the enum meanings and adds the ledger-consistency note for 'accrued', but most parameter information is already present in the schema.

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 states a specific verb and resource: build a governed analytics report over rebate data, with fixed measures and group-by dimensions. It clearly distinguishes itself from raw SQL by emphasizing the semantic layer, but it does not explicitly differentiate itself from siblings such as report, run_report, or list_reports.

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?

It gives a clear usage condition with examples: use when the user asks to see, analyze, or break down their rebates. It also states the account prerequisite, but it does not describe when not to use this tool or point to alternative report-related tools.

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