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

Annotations already cover the safety profile (read-only, idempotent, non-destructive), so the bar is lower, and the description still adds real behavior: add-backs are itemized with a parallel conservative case, double-counted adjustments are excluded, and multiples must come from the user. It stops short of describing validation failures or how the conservative case is derived beyond the refusal of double-counts.

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, front-loaded with the core operation and each carrying distinct information (what it computes, when to use, what it won't do). The parenthetical phrase 'with a conservative case alongside' is slightly clunky, and the return-value sentence is partly redundant with the output schema.

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 nine-parameter, single-required-input computation tool with a full output schema, the description covers the operation, the user intent that selects it, the user-supplied multiple constraint, and the exclusion of industry multiples. Nothing an agent needs to invoke it correctly is missing, and the accurate output listing is harmless redundancy.

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 coverage is 100%, so the baseline is 3; the description earns a point by conveying the relationship between inputs — the conservative case maps to includeInConservative, and the multiple range is explicitly user-supplied rather than inferred. It does not explain the bridge deductions or the basis enum beyond what the schema already documents.

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 names a specific verb and resource — normalize earnings into SDE, bridge to debt-service cash flow, apply a user-supplied multiple range — and the domain (valuation math) is clearly distinct from the financing-oriented siblings (build_capital_stack, model_acquisition_loan, screen_sba_eligibility). It also states a negative scope boundary: 'The tool does not supply industry multiples.'

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?

'Use when the user asks what the earnings are or what the business is worth on them' gives an explicit triggering condition rather than implied usage. The exclusions are partial — it rules out supplying multiples but does not say when a sibling (e.g. check_deal_affordability) should be reached for instead.

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