time_value_calc

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

The annotations declare readOnlyHint=true, indicating the tool should be read-only. However, the description states 'except for methods that may write results when integrated into workbook workflows,' which suggests possible write side effects. This directly contradicts the readOnlyHint annotation. The description provides no further details about permissions, side effects, or what 'integrated into workbook workflows' means.

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 with clear sections for Args, Returns, Raises, and Notes, and opens with a concise one-sentence summary. It is not overly verbose, though the Args list somewhat duplicates the schema. The structure aids 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 the tool's complexity (14 parameters, 6 operations, no output schema), the description is insufficient for correct invocation. It does not specify required arguments per operation, output formats, or provide examples. The ambiguous write behavior further undermines completeness. The Raises section indicates errors but does not detail what is required.

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 Args section groups parameters by operation type (e.g., rate/nper/pmt/pv/fv for financial calculations, cost/salvage/life for depreciation, cash_flows for IRR), adding some meaning beyond the bare schema. However, it does not explain parameter defaults like when='end', guess=0.1, or method='sln', nor does it specify which parameters are required for each operation. Since schema description coverage is 0%, the description partially compensates but not fully.

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 states it performs time-value-of-money calculations and depreciation methods, listing specific operations like fv, pv, nper, rate, depreciation, and irr. This provides a specific verb+resource combination. However, it does not explicitly distinguish itself from sibling financial tools like loan_amortization or dcf_analysis, so it lacks full sibling differentiation.

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?

There is no guidance on when to use this tool versus alternatives such as loan_amortization or dcf_analysis. The description only states what it does and lists operations, but does not provide context on selection criteria or exclusions. The note about write behavior is not usage guidance.

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