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

The annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false, providing the core safety profile. The description adds no side-effect information but does describe the output (quality, ruler, local clock bounds) and the input basis (sunrise/sunset at a location), which gives some behavioral context beyond the annotations. Since annotations cover the main safety aspects and the description adds modest context, a score of 4 is appropriate.

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 main description is a single, dense sentence that conveys the core function without fluff. The additional sections (WORKFLOW, INPUT CONTRACT, DO NOT CONFUSE WITH) are each short and purposeful, adding necessary guidance without redundancy. The structure is well-organized and every sentence contributes value.

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?

The description covers the tool's purpose, input constraints (via INPUT CONTRACT and schema), output expectations (quality, ruler, clock bounds), workflow (before/after), and alternatives to avoid. It also provides a link to the full output/error contract. For a tool with a nested location parameter, this is comprehensive and leaves little ambiguity for an agent to invoke it correctly.

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% with all fields having descriptions (e.g., lat/lon ranges, date pattern, timezone default, response_format enum). The description text adds context by explaining that the location is used for 'sunrise/sunset' and that output includes 'local clock bounds,' which clarifies the role of timezone and lat/lon. The INPUT CONTRACT section also states that LocationInput enforces date format and lat/lon ranges, reinforcing schema details. This extra context justifies a 4 rather than the baseline 3.

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 states exactly what the tool does: 'Splits a solar day into sixteen Choghadiya segments from sunrise/sunset at a location and labels each slot's quality, ruler, and local clock bounds.' It clearly identifies the resource (solar day segments) and the action (splits and labels). The 'DO NOT CONFUSE WITH' section explicitly differentiates it from asterwise_get_hora and asterwise_get_muhurta, making it distinct among the many sibling tools.

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 provides explicit workflow guidance: 'BEFORE: None — this tool is standalone. AFTER: asterwise_get_rahu_kaal — optional inauspicious band overlay for the same date.' It also includes 'DO NOT CONFUSE WITH' warnings that clarify when not to use this tool compared to related ones (hora, muhurta). This gives the agent clear conditions for selecting this tool over alternatives.

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