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

The description adds meaningful behavior beyond the annotations by stating the result is random, that 'maybe' can be included, and that the output is the answer. Annotations already cover the read-only, non-destructive, idempotent nature, so the description does not need to repeat that safety profile.

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 short, front-loaded with the core purpose, and ends with the return value. The source URL is somewhat extraneous for an agent selecting the tool, but it does not significantly dilute the message.

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 tool with one optional parameter, a clear output statement, a read-only annotation set, and an output schema, the description covers everything an agent needs to decide and invoke correctly. No required context is missing.

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%, and the allowMaybe parameter is already fully documented in the schema. The description's 'optional maybe' is consistent but does not add new semantic detail beyond what the schema provides, so the baseline of 3 applies.

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 what the tool does: 'Get a random yes or no decision, with an optional maybe.' It identifies a specific verb, resource, and output. It does not explicitly name or contrast sibling tools like hopi_coin_flip or hopi_magic_8_ball, but the yes/no scope is specific enough to be unambiguous.

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?

Usage context is implied: this is the tool for random yes/no decisions, optionally including 'maybe.' However, there is no explicit guidance on when to choose it over similar random-decision siblings such as hopi_magic_8_ball, hopi_coin_flip, or hopi_fortune_cookie.

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