Astro Skill MCP Server

Calculate Kundali (Birth Chart)

calculate_kundali

Read-onlyIdempotent

Instructions

Compute a sidereal Vedic kundali (birth chart) from birth details: lagna, Moon rashi, nakshatra with pada, planet positions with sign and whole-sign house placements, navamsa (D9) and further divisional charts, ashtakavarga tables, and the Vimshottari dasha seed. Returns the kundali JSON that the dasha, gochar, compatibility, and report tools consume.

Input Schema

TableJSON Schema

Name	Required	Description	Default
`dob`	Yes	Date of birth, DD/MM/YYYY or YYYY-MM-DD.
`lat`	Yes	Latitude of the birth place in decimal degrees (north positive).
`lon`	Yes	Longitude of the birth place in decimal degrees (east positive).
`tob`	Yes	Time of birth, HH:MM (24-hour clock), local time at the birth place.
`place`	Yes	Birth place name; a label for output, not geocoded.
`ayanamsa`	No	Sidereal ayanamsa to calculate with. Default is Lahiri (Chitrapaksha).	lahiri
`timezone_name`	Yes	IANA timezone of the birth place, e.g. Asia/Kolkata.

Schema Changelog

Changes observed during successful MCP inspections.

Addedv1.1.1Jul 23, 2026
Removedv1.1.0Jul 18, 2026

Changed8 schema fields changedv1.0.1Jul 13, 2026

addedInput schema / properties / ayanamsa / description

Added value: +"Sidereal ayanamsa to calculate with. Default is Lahiri (Chitrapaksha)."

addedInput schema / properties / ayanamsa / enum

Added value: +[
+  "lahiri",
+  "chitrapaksha",
+  "raman",
+  "krishnamurti",
+  "kp",
+  "fagan_bradley",
+  "true_chitra",
+  "yukteshwar"
+]

addedInput schema / properties / dob / description

Added value: +"Date of birth, DD/MM/YYYY or YYYY-MM-DD."

addedInput schema / properties / lat / description

Added value: +"Latitude of the birth place in decimal degrees (north positive)."

addedInput schema / properties / lon / description

Added value: +"Longitude of the birth place in decimal degrees (east positive)."

addedInput schema / properties / place / description

Added value: +"Birth place name; a label for output, not geocoded."

addedInput schema / properties / timezone_name / description

Added value: +"IANA timezone of the birth place, e.g. Asia/Kolkata."

addedInput schema / properties / tob / description

Added value: +"Time of birth, HH:MM (24-hour clock), local time at the birth place."

First observedv1.0.0Jul 13, 2026

TDQS

A4.2/5.0

Behavior4/5

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

Annotations already declare readOnlyHint, idempotentHint, destructiveHint=false, and a closed-world scope, so the safety profile is covered. The description adds real value beyond that by disclosing the exact contents of the returned JSON and its role as a shared input for downstream tools, which is the key behavioral trait an agent needs here.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness4/5

Is the description appropriately sized, front-loaded, and free of redundancy?

Two sentences, front-loaded with the action and payload, with no filler. The output enumeration is dense but each listed artifact is decision-relevant, so it largely earns its place, though it could be trimmed slightly.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness5/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

No output schema exists, and the description compensates by enumerating the return payload and stating which sibling tools consume it. Combined with 100% parameter coverage and clear annotations for a read-only computation, an agent has everything needed to call and sequence this tool.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters3/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema description coverage is 100%, including formats for dob/tob, decimal-degree conventions for lat/lon, the IANA timezone requirement, the non-geocoded nature of place, and the ayanamsa enum with default — so the schema carries full parameter meaning. The description adds nothing beyond the vague phrase 'birth details', matching the baseline 3.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose5/5

Does the description clearly state what the tool does and how it differs from similar tools?

Specific verb (compute) plus resource (sidereal Vedic kundali/birth chart) and an explicit enumeration of the computed artifacts: lagna, Moon rashi, nakshatra with pada, planet positions, D9 and divisional charts, ashtakavarga, and the dasha seed. The closing sentence distinguishes it from siblings by naming the tools that consume its output (dasha, gochar, compatibility, report).

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines4/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

The final sentence makes the usage context clear: this is the upstream generator whose JSON feeds calculate_dasha, calculate_gochar, calculate_compatibility, and the report tools, implying it must be run first. It does not explicitly exclude alternatives (e.g. parse_birth_details, calculate_panchang), so it stops short of full when-not guidance.

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

Deploy Server

Calculate Kundali (Birth Chart)

Instructions

Input Schema

Schema Changelog

TDQS

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