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

Annotations already declare readOnly, idempotent, non-destructive and closed-world, so the safety profile is covered. The description adds operationally useful metadata the annotations do not carry — the POST endpoint and the 10-credit Tier 1 cost — but says nothing about response size or behavior.

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?

Extremely short and front-loaded: the scope statement comes first, followed by clearly bracketed group/endpoint/cost tags. There is no waste, though the body text is thinner than ideal.

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 annotations cover safety. What is missing is routing guidance versus the other rune tools and any indication of result shape, leaving the definition only minimally sufficient.

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%, so 'fields' and 'precision' are already fully documented in the schema. The description contributes no parameter meaning beyond that, which is the baseline when the schema does the work.

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 phrase 'All 24 runes' names the resource and its scope, which does distinguish it from siblings like astroway_runes_single, _three, _nine and _by_zodiac. It lacks a verb ('list', 'retrieve') and sibling names, but the scope contrast is implicit and usable.

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 when-to-use guidance at all. An agent must infer from the number '24' that this is the full-list alternative to runes_single/three/nine, with no explicit routing rule or exclusions.

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