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

Annotations already declare the safe read-only, idempotent, non-destructive profile, so the bar is lower. The description adds one genuinely useful behavioral fact — the cost (10 credits, Tier 1) — but says nothing about slug format requirements, rate limits, or the input cap, which would matter for a paid call.

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?

Front-loaded and tight: the core action leads, the alternative follows, and the group/cost metadata is compact. No filler sentences, though the bracketed metadata tags cost a little space.

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 needn't be explained. The description covers purpose and cost, but leaves slug format, the 15-card cap, and 'question' semantics unstated, which is a modest gap for a paid tool whose sole job is resolving inputs.

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 50%: 'fields' and 'precision' are documented in the schema, while 'cards' and 'question' have no schema description. The description adds some value by specifying the input is card 'slugs,' clarifying the array-of-strings parameter, but adds nothing for 'question' and not enough to compensate fully. Baseline 3 is appropriate.

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 ('resolve a list of card slugs into structured meanings') and distinguishes the tool from the narrative AI interpreters by pointing to '/interpret/*' for full narrative. It does not explicitly name its nearest sibling (astroway_tarot_marseille_interpret or the RWS keyword/card lookup tools), so differentiation is partial.

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 parenthetical '(use AI /interpret/* for full narrative)' gives an alternative-use hint, implying this tool is for raw structured meanings rather than prose. However, it gives no guidance on when to choose it over the many other RWS tools (cards_slug, keywords, spreads) and provides no exclusions or prerequisites.

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