Aspect Matrix

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

Annotations already carry the read-only/idempotent/closed-world profile, so the description only needs marginal additions — and it delivers: it discloses the calculation method (per-pair astro.com orb matrix), the output fields, the endpoint, and a 10-credit cost. The cost and method disclosure are genuinely useful context not present in structured fields.

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 core sentence is front-loaded and information-dense, with the /chart comparison placed immediately after for contrast. The bracketed metadata block (group, endpoint, required, cost) is scaffold-like but short and scannable; 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?

An output schema exists, so return values needn't be spelled out, and purpose/method/cost/endpoint are covered. But for a 13-parameter tool with weak schema coverage, the undefined optional parameters (zodiacType, houseSystem, ayanamsa variants, cosmogram) are a real gap — an agent can't tell which ones actually affect an aspect-only calculation.

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 23% across 13 parameters, and the description adds almost nothing: it repeats the required list (date, time, latitude, longitude) already encoded in the schema and is silent on ayanamsa, ayanamsaId, zodiacType, houseSystem, cosmogram, timezoneOffset, and name/city. For a low-coverage schema the description should compensate, and it does not.

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?

It states a specific verb and resource — a standalone aspect calculation returning the full inter-planetary aspect list — and names the sibling it deliberately is not ('same calcAspects() as /chart but without planet positions / houses / midpoints overhead'). It does not differentiate against the other aspects_* siblings (aspect_timeline, aspect_grid, antiscia, midpoints), so an agent must infer from scope words 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 contrast with /chart implies when this tool is preferable (you want aspects only, not a full chart), but there is no explicit when-to-use/when-not statement and no routing among the several aspect-oriented siblings. Usage is left to inference.

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