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

No annotations are supplied, so the description carries the full behavioral burden. 'Look up' strongly implies a non-mutating read, and the enumeration of returned fields (keywords, upright/reversed, topic readings, yes/no) gives real transparency about output shape. It is silent on behavior for unrecognized card names, on whether matching is fuzzy, and on latency/limits, which matters more here precisely because there are no annotations.

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, no filler, and the core purpose is front-loaded ahead of the supported input formats. The content list is a bit dense but each clause maps to a real return field, so nothing is wasted.

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 no output schema and no annotations, the description does the heavy lifting well: it names the returned facets and the accepted input shapes. The remaining gaps are error behavior for unknown cards and the meaning of the orientation default, which is a modest but real omission for a four-parameter 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 coverage is 75%, with card, topic and language documented but orientation left bare. The description compensates usefully by supplying additional accepted name formats ('3 of Cups', 'Queen of Swords', 'ace of coins') beyond the schema's examples, signalling tolerant, case- and article-insensitive matching. The mention of 'upright and reversed meaning' also hints at orientation behavior, though it does not explain the default 'both' or the language switch.

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 definition opens with a specific verb and resource ('Look up the meaning of a tarot card') and then enumerates the exact content returned: keywords, upright/reversed meaning, love/feelings/career/money readings, and yes/no lean. That is far more informative than the title alone. It stops short of naming the sibling it differs from (draw_tarot_cards), so an agent must infer that this one retrieves an existing card's interpretation rather than drawing a new spread.

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 is only implied: 'look up' suggests a retrieval task once a card is already known, which distinguishes it in spirit from draw_tarot_cards, but the description never says when to pick this over drawing. There are no explicit exclusions, prerequisites, or fallback guidance for unknown card names.

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