cost_reimbursable_billable_transactions

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

No annotations are provided, so the description carries full burden. It clearly states this is a summarization (read/aggregate) operation returning summed amounts and date ranges, which is useful behavioral context. However, it doesn't disclose potential pagination/limits, whether zero-result projects are excluded, or any access/permission requirements. For a summarization tool that is inherently non-destructive, the described behavior is reasonably transparent, but it could specify more about filtering semantics and aggregate output details.

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 well-structured and front-loaded: purpose is stated in the first line, then the WHERE criteria, then the aggregation behavior, then the params doc. The parameter section is useful but somewhat verbose - the Python docstring formatting adds lines without much new info beyond the schema titles. It's efficient and free of fluff.

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?

No output schema exists, so the description must explain return values, and it does: 'Per-project sums of billable amounts with min/max accounting dates.' The filter criteria (ANALYSIS_TYPE='BIL', BI_DISTRIB_STATUS='N') are fully documented, and the four parameters are each described with types and formats (e.g., YYYY-MM-DD). For a 4-param summarization tool with no annotations or output schema, this is quite complete. Minor gaps: doesn't describe the exact output structure (field names) or whether it returns zero rows or excludes unmatched projects.

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 0%, so the description MUST compensate, and it does excellently. Each of the four parameters gets a clear explanation including their types, optionality, meaning (business unit code, project ID, accounting date bounds), and date format (inclusive, YYYY-MM-DD). The description adds meaning beyond the schema's bare null/default defaults, making all filter parameters actionable and self-documenting.

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 opening line is a specific verb+resource: 'Summarize undistributed cost-reimbursable billable transactions.' The first sentence precisely scopes what qualifies (PROJ_RESOURCE rows with ANALYSIS_TYPE='BIL' and BI_DISTRIB_STATUS='N') and what the output is (per-project summed BIL amounts and min/max accounting dates). This clearly distinguishes it from the sibling tools (e.g., get_bill_plan, list_contracts, check_project_billing_setup) which operate on different concepts.

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 clearly explains what the tool does and the filter semantics, which implies when to use it (when you need undistributed billable transaction summaries by project). However, it provides no explicit exclusions or alternatives relative to siblings—there's no statement like 'for distributed transactions use X' or 'for detailed line items use Y.' Given the sibling set includes billing-related tools like get_bill_plan and check_project_billing_setup, explicit differentiation would help agents pick correctly.

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