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

With no annotations, the description must disclose behavioral details. It only states that it calculates expected value and returns lose_probability. It omits critical traits like how it handles invalid inputs, whether it assumes risk neutrality, or edge cases (e.g., zero probabilities).

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 two sentences, each serving a clear purpose: stating the tool's function and pointing to related resources. No unnecessary words or redundancy.

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 that an output schema exists (mentioned in context signals), the description can rely on it for return values. The tool is relatively simple with four parameters. The description covers the purpose and a slight hint for alternatives, but it does not mention the primary return value (expected value) explicitly, assuming the output schema fills that gap.

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 description does not need to repeat parameter details. However, it adds no extra semantic context beyond the schema. The mention of lose_probability in the description pertains to output, not parameters.

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 the tool's function: calculating expected value and profitability of a bet or investment. It distinguishes itself from siblings by specifying its domain (bet/investment) and referencing related calculators via list_bundles.

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 provides minimal usage guidance. It mentions seeing list_bundles for related calculators but does not elaborate on when this tool is appropriate versus alternatives, nor does it include prerequisites or hints for proper use.

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