ephemeris_angles_points

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

Annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false, covering the safety profile. The description adds the credit cost ('1 credit per call'), which is useful operational context. It does not contradict annotations and provides additional value beyond the 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 description is concise: two sentences, with the essential purpose front-loaded and the credit cost as a separate clear line. Every word earns its place, with no fluff or redundancy.

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 simple calculation tool, the description is sufficiently complete: it names the input (date/time, location) and the output (specific angles/points). No output schema exists, but the description implies return values through the listed points. It could mention edge cases or output format, but these are not critical for a straightforward ephemeris calculator.

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 the schema already documents all parameters clearly. The description adds minimal semantics beyond stating 'given date/time and location', which aligns with the schema. Baseline 3 is appropriate since the description does not need to compensate.

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 description uses a specific verb ('Calculate') and a clear resource ('chart angles and sensitive points') followed by explicit examples (ASC, MC, DSC, IC, Vertex, East Point). This distinguishes it from sibling tools like ephemeris_house_cusps or ephemeris_planet_position, which target different data.

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 clearly states what the tool computes (angles and sensitive points for a given date/time and location), providing clear context. However, it does not explicitly mention when to prefer this over alternatives or list exclusions, so it falls short of a full 5.

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