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

Annotations already communicate readOnlyHint=true, so no side-effect warning is needed. The description adds useful behavioral context beyond annotations: it returns all three representations at once and specifies that American odds carry no commas (e.g., +441 or -200). This helps the agent set expectations about output formatting.

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 compact: one purpose sentence, one outcome sentence, and a short list of use-case examples. Every sentence earns its place, the main behavior is front-loaded, and there is no redundant restating of the tool name or 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 simple two-parameter conversion tool with full schema coverage and a read-only annotation, the description is largely complete. It states inputs, output behavior, and formatting conventions. The only minor gap is that it does not specify the exact response structure or key names, but 'get all three back' is sufficient for most agent workflows.

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 baseline is 3. The description adds value beyond the schema with concrete examples like '+150', '62%', and '2.5', and clarifies the American odds formatting constraint. This helps an agent understand accepted value forms without relying on enum hints alone.

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 opens with a specific verb and resource: 'Convert between implied probability, American odds, and decimal odds.' It also states the exact outcome—'get all three back'—and gives concrete user-phrase examples that remove ambiguity. No sibling tool overlaps with this conversion purpose, so it is clearly distinguishable.

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 explicit usage contexts: 'Use for "what is +150 as a probability"', 'convert 62% to American odds', and 'decimal to implied odds.' These examples tell an agent when to invoke the tool. It does not explicitly state when not to use it or name alternatives, but the sibling list contains no competing conversion tool.

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