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

Annotations already declare readOnlyHint=true, destructiveHint=false and openWorldHint=true, so the safety profile is covered. The description usefully adds the cost (100 credits, Tier 4) and the endpoint, which annotations do not provide. It does not explain why idempotentHint is false for a read-only call, nor what the AI explanation entails.

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?

The description is short and front-loads the purpose before the bracketed metadata. The bracketed group/endpoint/required/cost lines are slightly noisy but each carries compact information, so there is little waste.

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. But for a 5-required-parameter tool with a near-twin sibling, the description omits the disambiguation, parameter usage, and cost implications an agent needs before committing. It is minimally adequate rather than complete.

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 only 38%, so the description should compensate, but it merely restates the five required parameter names that the schema already marks required and says nothing about what transitPlanet, natalPlanet, aspectType accept or how the optional fields/precision/language parameters behave. It adds no meaning beyond the schema.

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: 'Explain a current transit hitting your natal chart.' An agent can grasp the purpose immediately. However, it never distinguishes itself from the close sibling astroway_mcp_ai_explain_aspect, leaving the borderline case ambiguous.

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, no exclusions, and no comparison to the near-identical sibling astroway_mcp_ai_explain_aspect. The '[Required: ...]' and '[Cost: ...]' lines are metadata, not routing guidance. The agent gets no help deciding between this and other AI tools.

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