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

Annotations already declare readOnly, idempotent, non-destructive, and closed-world behavior, so the safety profile is covered. The description's only added behavioral fact is the cost (10 credits, Tier 1), which is genuinely useful, but it says nothing about what the response contains or how the 90° dial projection is applied.

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 short bracket lines plus one sentence; the operative clause is front-loaded and there is no filler. It is terse to the point of under-specification, but nothing is padded.

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 20-parameter, 5-required-parameter tool this is too thin. An output schema exists so return values need not be explained, but the description omits when to use it, how natal vs transit data are supplied, and what the many optional flags do.

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?

Twenty parameters with only 25% schema description coverage, and the description contributes zero parameter information. Core required inputs (date, time, latitude, longitude, targetDate) have no descriptions in either place, and flags like cosmogram, converse, withTnp, and the 25-value houseSystem enum are unexplained.

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+resource: transits contacting natal midpoints within the 90° dial, which is a recognizable cosmobiological operation. It does not explicitly distinguish itself from close siblings such as astroway_cosmobiology_midpoint_pictures or astroway_cosmobiology_dial_90, so an agent must infer the boundary from names alone.

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 description gives no when-to-use guidance, no prerequisites, and no named alternative. Nothing tells the agent when this tool is preferable to dial_90, midpoint_pictures, or prognostics_transits.

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