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

Annotations already declare readOnlyHint, idempotentHint, non-destructive and closed-world, so the safety profile is covered. The description does add genuinely useful context beyond them — that the card is date-seeded and therefore stable within a day — plus the 10-credit cost, which annotations do not convey.

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 compact lines with the substantive claim (date-seeded, deterministic) front-loaded and metadata relegated to tags. No filler, though the brevity comes partly from under-specification rather than tight editing.

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 described, and cost plus determinism are disclosed. What is missing is the behavior of the optional date parameter (default to today?) and any tie-in to sibling daily/draw tools, which matters given the very large tool surface.

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 67%: fields and precision are documented in the schema, while date carries only a regex pattern and no prose. The description's phrase 'based on date seed' hints that date drives the result but adds no format or default behavior beyond the schema's pattern.

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?

Names the resource (Rider-Waite-Smith daily card) and the operative mechanism (date seed, deterministic per day), and the RWS group tag separates it from astroway_tarot_marseille_daily and astroway_tarot_lenormand_daily. It stops short of naming a sibling explicitly, so it is clear but not fully differentiated.

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 word 'daily' plus 'deterministic per day' implies the intended cadence, but nothing states when to pick this over astroway_tarot_rider_waite_draw_single or the other draw_* tools, nor what happens if no date is supplied.

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