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

Annotations provide readOnlyHint, so the description adds value by explaining the computational approach (BSM expected value vs premium) and the concept of edge-maximizing bet size. This goes beyond the annotation and gives insight into how the tool behaves without contradicting the read-only hint.

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 sentences, about 25 words, with the purpose front-loaded in the first sentence and the method in the second. Every word earns its place with no fluff or repetition.

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?

The description explains what the tool does and its method, but does not specify the output format (e.g., whether the result is a fraction of capital) or any assumptions/caveats. With no output schema, this is a notable gap for a parameter-heavy calculation tool.

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 documents all 8 parameters. The description does not add parameter-level meaning beyond mentioning 'premium' and 'expected value' conceptually. Baseline 3 is appropriate as the schema fully covers parameter semantics.

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 computes Kelly criterion optimal position sizing for option trades, using a specific verb 'compute' and resource. It distinguishes itself from sibling tools like calculate_greeks and solve_iv by focusing on Kelly sizing and BSM expected value vs premium.

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 gives clear context that the tool is for option trades and uses BSM expected value vs premium to find edge-maximizing bet size. It implies when to use it (when sizing option positions) but does not explicitly mention alternatives or exclusions compared to sibling tools, so it misses the top score.

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