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

With no annotations, the description carries the full burden, and it discloses the calculation method (sidereal/Lahiri, professional-grade engine) and the exact return shape. It does not state whether input time is local or UTC beyond the timezone_offset param, nor any constraints on date ranges, which leaves a behavioral gap for a computation-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?

Labeled sections (WHEN TO USE / WHAT IT DOES / RETURNS / NEXT) make it skimmable and front-loaded, with no redundant or filler sentences. Every line carries actionable content.

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 an 8-param, output-schema-backed calculation tool with no annotations, the description covers purpose, invocation context, and downstream routing well. The remaining hole is parameter interpretation (time basis, geo defaults), which is the one thing an agent can most easily get wrong.

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 0% and the description adds nothing about the 8 parameters. It never explains that hour/minute are local clock time interpreted via timezone_offset, nor the meaning of the India-centric latitude/longitude defaults, so an agent must guess at the most error-prone inputs.

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 names a specific verb+resource ('Calculate a complete Vedic birth chart (Kundli)') and scopes it precisely (high-precision sidereal positions, Lahiri ayanamsa). This distinguishes it from siblings like calculate_varga_charts or calculate_all_dashas, which build on the chart rather than produce it.

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 WHEN TO USE block gives a clear triggering condition (needing a chart to analyze planets, houses, nakshatras, yogas) and the NEXT line routes to calculate_vimsottari_dasha/ask_cosmic_advisor as downstream consumers. It stops short of explicit exclusions, e.g. telling the agent not to call this when only a dasha or transit is needed.

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