Single Rune Draw

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

Annotations already declare readOnlyHint=true, destructiveHint=false, and idempotentHint=true. The description adds the term 'Deterministic', which aligns with idempotency but doesn't go beyond. It does not describe what happens if no seed is provided (random?), the effect of 'allowReversed', or the return format. With annotations covering safety, this is adequate but lacks detail.

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 extremely concise: a single sentence plus a group label and example. It is front-loaded with the core purpose ('Deterministic 1-rune draw') and contains no superfluous information. Every element earns its place.

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?

With 3 parameters at 0% schema coverage and no output schema, the description is too minimal. It does not explain the output format (e.g., rune name, reversed status, interpretation), how 'date' influences the draw, or the effect of 'allowReversed'. Given the tool's simplicity, more context could be added without verbosity.

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 0%, yet the description only mentions the 'seed' parameter via an example. The 'date' and 'allowReversed' parameters are completely undocumented. The description does not compensate for the lack of schema descriptions, leaving the agent to infer their purpose from names 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?

Title 'Single Rune Draw' and description 'Deterministic 1-rune draw' clearly state the tool's purpose. Among sibling tools like 'runes', 'runes_three', 'runes_nine', etc., this one is distinct as a single rune draw. The group label 'Elder Futhark Runes' further specifies the rune set.

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 no guidance on when to use this tool versus alternative rune tools (e.g., 'runes_three', 'runes_nine'). It does not specify if the seed is required, how the date parameter affects the draw, or when deterministic behavior is important. No explicit when-to-use or when-not-to-use information is given.

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