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

Annotations already declare readOnly/idempotent/non-destructive/closed-world, so the safety profile is covered. The description adds genuinely new behavioural context: the endpoint (GET /v1/tarot/lenormand/cards), the group, and a concrete cost of 10 credits (Tier 1) that the agent needs for budget decisions. No pagination or caching behaviour is disclosed, but the credit cost is a meaningful addition beyond 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?

Four short lines: resource first, then bracketed metadata for group, endpoint and cost. Nothing is wasted and the key noun is front-loaded. It is arguably too terse rather than too long, but structurally it is clean.

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?

For a simple read-only catalogue endpoint with an output schema, full parameter coverage and annotations covering safety, most of what an agent needs is present. The missing piece is routing context — nothing says this is the static deck reference versus the sibling cards_slug lookup or the draw_* spread tools, which is the main risk in a toolset this large.

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 description coverage is 100% and both parameters (fields, precision) are fully documented in the schema as generic 'compact mode' modifiers. The description adds nothing about them, which is acceptable given the schema does the work, so the baseline of 3 applies.

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 names a specific resource ('36-card Lenormand oracle deck'), which tells the agent this returns the full 36-card catalogue rather than a spread. However it is a bare noun phrase with no verb, and it does not distinguish itself from the obvious sibling astroway_tarot_lenormand_cards_slug (single-card lookup) or astroway_tarot_lenormand_draw_* (spread draws). Purpose is inferable but not stated.

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?

No when-to-use guidance and no mention of alternatives, despite ~30 Lenormand-related siblings in the toolset. The agent has to guess that this is a static reference lookup rather than a divination action. Nothing here is misleading, but nothing routes the caller either.

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