Marseille — Three-Card

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

Annotations already indicate readOnlyHint=true and destructiveHint=false, so the agent knows it's safe. The description adds the spread structure (three-card, past/present/future) and an example input, but does not explain behavior like reversals or seed determinism beyond the example. Some behavioral context is provided, but not comprehensive.

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: one line for spread purpose, one line for group, and one JSON example. Every sentence provides value without 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 the tool's simplicity (three-card draw with no output schema), the description covers the spread type and input example. However, it does not describe the output format (e.g., three cards, interpretations) or the role of the seed parameter in randomness. Annotations cover safety, so overall completeness is adequate but not excellent.

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?

The input schema has 100% coverage (single body parameter described), and the description gives a concrete example showing expected fields (seed, question, allowReversed). This adds meaning beyond the schema's generic description, helping the agent understand the required structure.

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 'Past / Present / Future three-card spread' with the group 'Tarot — Marseille', which distinguishes it from sibling tools like tarot_rider_waite_draw_three_card or tarot_lenormand_draw_three_card. The verb 'draw' is implied by the spread name, and the resource is explicit.

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 an example question ('What should I focus on?') but does not explicitly state when to use this tool versus alternative tarot spreads (e.g., single card, Celtic cross). No guidance on exclusions or prerequisites is given.

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