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

Beyond the annotations (readOnlyHint, idempotentHint, destructiveHint), it discloses that partially paid invoices are excluded from money totals and explains why, and lists a broad set of never-returned data categories. This gives an agent strong expectations and prevents attempts to retrieve detail.

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 with no filler: purpose, key aggregation caveat, and explicit output exclusions. The necessary caveats are front-loaded and each sentence carries information.

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 a single parameter and an output schema, the description provides enough context: scope, aggregate-only behavior, and explicit non-inclusion list. No critical usage gap remains.

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?

The schema already documents businessId with 100% coverage; the description only restates the 'one tenant-owned business' scope, adding no extra format or semantic detail. Baseline 3 is appropriate given high schema 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 states a specific verb ('Summarize') on a specific resource ('receivables') with defined scope (open, overdue, age-bucketed, one tenant-owned business). The title and description align, and the tool is clearly distinct from sibling summary tools like get_revenue_summary or get_quote_pipeline_summary.

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 implies use when an aggregate receivables view for a business is needed, but offers no explicit comparison to siblings or conditions for choosing get_revenue_summary or get_quote_pipeline_summary. It provides context on output limits but no 'when not to use' guidance.

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