calculate_sky_chart

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

Annotations already declare readOnly/idempotent/non-destructive, and the description adds meaningful context beyond them: 'Server checks run before successful results are returned', the mandatory post-call verification loop, the caveat that psychological interpretations are not checked, and the precise effect of detail_level on rows and truncation marking. This is rich behavioral disclosure for a read-only tool.

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?

Dense but front-loaded: the resource and returned content come first, then the verification constraint, then parameter behavior. Each sentence carries information, though the verification instructions are somewhat verbose and could be tightened.

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?

With no output schema, the description compensates by enumerating returned content and explaining detail_level/truncation semantics, plus the verification protocol. The main gap is location_id/place handling, which an agent must call correctly but receives no guidance on.

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?

moment gets format detail absent from the schema ('ISO 8601 with a timezone offset; defaults to now'), and detail_level/include are explained thoroughly. However, location_id is left entirely undocumented in both schema and description, and 'place' is only alluded to, so coverage of the 4 params is incomplete.

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 ('full chart cast for any moment and place') and enumerates the returned content (planets, Placidus houses, axes, aspects, aspect patterns, lunar phase, planetary motion). It explicitly distinguishes from birth-chart tools ('rather than for a birth'), but does not name the close siblings get_current_sky or render_sky_chart, leaving differentiation to inference.

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?

Gives concrete guidance on the verification workflow ('before interpreting this data, call verify_calculation_claims with its unchanged calculation_reference...') and on when to use detail_level=summary vs omit both. However, it never states when to prefer this over get_current_sky or render_sky_chart, which are the most likely alternatives an agent would weigh.

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