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

Annotations already declare readOnly=true, idempotent=true, destructive=false, and closed-world, so the safety profile is covered. The description adds the date-seed determinism (same date yields the same draw) and the 10-credit cost, which is useful for call planning, but says nothing about the response contents or what happens when date is omitted.

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?

One front-loaded sentence carries the meaning, with the group/endpoint/cost metadata stacked below in a scannable format. Nothing is padded, though the bracket lines are boilerplate rather than descriptive content.

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?

An output schema exists, so return values need not be explained, and annotations cover safety. The remaining gap is behavioral: with all four parameters optional, the description never states whether omitting date defaults to today, which is the key question for a daily-draw 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%: art, fields, and precision are documented in the schema, while date carries only a pattern and no prose description. The phrase 'based on date seed' partially fills that gap by implying date drives the draw, but it does not state the default when date is omitted, which matters for a zero-required-parameter tool.

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?

States a specific verb and resource ('Daily three-card draw') and adds the distinguishing mechanism ('based on date seed'), which separates it from a generic three-card spread. It does not, however, explicitly contrast with the nearby sibling astroway_tarot_lenormand_draw_three_card, so the agent must infer the difference from the name alone.

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?

There is no explicit when-to-use guidance and no named alternative. 'Daily' implies a recurring date-based reading, but nothing states when to prefer this over astroway_tarot_lenormand_draw_three_card, astroway_tarot_marseille_daily, or the other daily-draw siblings. The bracket lines give an endpoint and cost, not usage guidance.

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