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

With no annotations, the description carries the full behavioral burden. It does add real value by disclosing a downside/stress dimension ('what happens if it underperforms'), which is not visible in the schema. It is silent, however, on modeling assumptions (constant profit, taxes, amortization vs interest-only) and on how results are expressed, which matters for a five-input financial model.

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?

Two tightly written sentences that front-load the core computation and then the input set. No filler, no restatement of the tool name, and the affordability question is stated first.

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?

There is no output schema and no annotations, so the description is the only source of behavioral context. It explains the question being answered but not the shape or components of the answer (e.g., whether profit covers debt service, the shortfall amount, sensitivity results). Adequate to trigger the tool, thin for interpreting or trusting the result.

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 defines every parameter including the key nuance that annualProfit is 'before financing'. The description restates the same four input categories at a conceptual level without adding units, defaults, or per-parameter meaning beyond the schema. Baseline 3 is appropriate.

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 analytical question ('can I afford to buy this business?') and the exact inputs it reasons over: asking price, deposit, loan terms and annual profit. That is a clear verb+resource far beyond the tool name. It does not, however, reference or distinguish itself from siblings like forge_business_valuation_estimate or forge_break_even, so it stops short of a 5.

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 context is implied by the phrasing 'can I afford to buy this business?', which an agent can map to an acquisition-affordability scenario. There is no explicit when-to-use/when-not statement and no named alternative among the finance siblings, so the guidance remains inferential.

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