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NatalChart.AI Astrology

by natalchart.ai · remote · no sign-in to list tools · v1.0.0 · published by ai.natalchart

Swiss Ephemeris astrology: natal charts, transits, synastry, solar returns and astrocartography.

Final · 2Changes · 8
CompareRegistry entry

10 tools: 2 do something that can't be undone and 8 change things.

Scanned Oct 21, 2026

2 checks matched something in the tool definitions. No finding is not a safety guarantee. How the checks work.

claude mcp add --transport http astrology https://www.natalchart.ai/mcp --header 'Authorization: <your-authorization>'

Findings

Matches of fixed checks, with the text they matched.

2 warn
  • Warntransits

    The server marks "transits" read-only (readOnlyHint: true), and its own name, description or input give the class "irreversible".

    Matched text

    annotations: {"readOnlyHint":true,"idempotentHint":true,"openWorldHint":false}; The input addresses people (input.to): what it sends cannot be taken back.

    What this check looks for
  • Warnbest_days

    The server marks "best_days" read-only (readOnlyHint: true), and its own name, description or input give the class "irreversible".

    Matched text

    annotations: {"readOnlyHint":true,"idempotentHint":true,"openWorldHint":false}; The input addresses people (input.to): what it sends cannot be taken back.

    What this check looks for

Tools

Open a tool for its reasons and full description. Descriptions are the publisher's own words, shown as they are.

10 tools

Can't be undone 2Claude Code: ask
  • best_daysEvery day of a window of up to 62 days scored for one activity (general, business, romance, health, creative, travel, home, clarity): helping and hindering transits, Moon phase and…1 finding

    Why it is in this group

    • The input addresses people (input.to): what it sends cannot be taken back.
    • The server marks it read-only (readOnlyHint: true), but an annotation never lowers a class.

    Findings

    • Warn

      The server marks "best_days" read-only (readOnlyHint: true), and its own name, description or input give the class "irreversible".

      Matched text

      annotations: {"readOnlyHint":true,"idempotentHint":true,"openWorldHint":false}; The input addresses people (input.to): what it sends cannot be taken back.

      What this check looks for
    Description, as the server wrote it
    Every day of a window of up to 62 days scored for one activity (general, business, romance, health, creative, travel, home, clarity): helping and hindering transits, Moon phase and sign, void of course. The five best days first. (API Pro) Use it to pick dates for an activity within the next weeks.

    Annotations the server declares

    • title: Best days for an activity
    • readOnlyHint: true
    • idempotentHint: true
    • openWorldHint: false
  • transitsUp to 60 transit events in a window of up to 92 days, the most significant kept when there are more: exact transit-to-natal aspects by date, sign ingresses and stations.1 finding

    Why it is in this group

    • The input addresses people (input.to): what it sends cannot be taken back.
    • The server marks it read-only (readOnlyHint: true), but an annotation never lowers a class.

    Findings

    • Warn

      The server marks "transits" read-only (readOnlyHint: true), and its own name, description or input give the class "irreversible".

      Matched text

      annotations: {"readOnlyHint":true,"idempotentHint":true,"openWorldHint":false}; The input addresses people (input.to): what it sends cannot be taken back.

      What this check looks for
    Description, as the server wrote it
    Up to 60 transit events in a window of up to 92 days, the most significant kept when there are more: exact transit-to-natal aspects by date, sign ingresses and stations. (API Pro) Use it for forecasts over weeks or months (a year is four windows); for a single day use daily_transits.

    Annotations the server declares

    • title: Transits for a period
    • readOnlyHint: true
    • idempotentHint: true
    • openWorldHint: false
Changes things 8Claude Code: ask
  • best_citiesThe catalogue of major cities ranked for one chart, overall or by chosen life spheres, worldwide or in one region.No findings

    Why it is in this group

    • Nothing in its name or description says what it does, so it is counted as a write.
    • The server marks it read-only (readOnlyHint: true), but an annotation never lowers a class.
    Description, as the server wrote it
    The catalogue of major cities ranked for one chart, overall or by chosen life spheres, worldwide or in one region. (API Pro) Use it when the user asks where in the world to live, work or travel; it ranks major cities, optionally by life sphere or region.

    Annotations the server declares

    • title: Best cities for a chart
    • readOnlyHint: true
    • idempotentHint: true
    • openWorldHint: false
  • daily_transitsThe calculated day: the sky at noon UTC, the Moon's phase, the sky events of the coming week and, with birth data, every transit to the natal chart with its orb.No findings

    Why it is in this group

    • Nothing in its name or description says what it does, so it is counted as a write.
    • The server marks it read-only (readOnlyHint: true), but an annotation never lowers a class.
    Description, as the server wrote it
    The calculated day: the sky at noon UTC, the Moon's phase, the sky events of the coming week and, with birth data, every transit to the natal chart with its orb. No generated text. Use it for a day's horoscope or what is happening for someone now: send birth for a personal answer, leave it out for the general sky of that day.

    Annotations the server declares

    • title: Daily sky and transits
    • readOnlyHint: true
    • idempotentHint: true
    • openWorldHint: false
  • location_scoreOne place against one chart: the relocated angles, the planets on them with orbs, a score for each life sphere and an overall score.No findings

    Why it is in this group

    • Nothing in its name or description says what it does, so it is counted as a write.
    • The server marks it read-only (readOnlyHint: true), but an annotation never lowers a class.
    Description, as the server wrote it
    One place against one chart: the relocated angles, the planets on them with orbs, a score for each life sphere and an overall score. (API Pro) Use it when the user asks whether a specific city or place suits them; it needs a birth time and the place's coordinates.

    Annotations the server declares

    • title: Astrocartography for one place
    • readOnlyHint: true
    • idempotentHint: true
    • openWorldHint: false
  • natal_chartA natal chart from birth data.No findings

    Why it is in this group

    • Nothing in its name or description says what it does, so it is counted as a write.
    • The server marks it read-only (readOnlyHint: true), but an annotation never lowers a class.
    Description, as the server wrote it
    A natal chart from birth data. "part" picks what to return: full (everything: bodies with sign, degree, speed, retrograde flag and house; the angles; twelve Placidus cusps; aspects with orbs; element and quality balance; fixed-star contacts), short (Sun, Moon and Ascendant, each body's sign, retrograde bodies, dominant element and quality), or one part: planets, angles, houses, aspects, elements, fixed-stars. Full by default. Use it whenever the user gives a birth date, time and place and asks about their chart, signs, houses or aspects, and before interpreting anything; part=short is enough for the Sun, Moon and rising sign.

    Annotations the server declares

    • title: Natal chart
    • readOnlyHint: true
    • idempotentHint: true
    • openWorldHint: false
  • skyPlanetary positions, Moon phase and the coming week's sky events for a date (?date=YYYY-MM-DD, today by default).No findings

    Why it is in this group

    • Nothing in its name or description says what it does, so it is counted as a write.
    • The server marks it read-only (readOnlyHint: true), but an annotation never lowers a class.
    Description, as the server wrote it
    Planetary positions, Moon phase and the coming week's sky events for a date (?date=YYYY-MM-DD, today by default). Use it for where the planets are on a date, the Moon phase, or the coming retrogrades and ingresses, when no one's chart is involved.

    Annotations the server declares

    • title: Sky for a date
    • readOnlyHint: true
    • idempotentHint: true
    • openWorldHint: false
  • solar_returnThe solar return chart for a year, cast for the birth place or another location.No findings

    Why it is in this group

    • Nothing in its name or description says what it does, so it is counted as a write.
    • The server marks it read-only (readOnlyHint: true), but an annotation never lowers a class.
    Description, as the server wrote it
    The solar return chart for a year, cast for the birth place or another location. (API Pro) Use it for the year ahead from a birthday; it needs a birth time.

    Annotations the server declares

    • title: Solar return
    • readOnlyHint: true
    • idempotentHint: true
    • openWorldHint: false
  • synastryTwo charts compared: inter-chart aspects with orbs, house overlays both ways and a score per life sphere.No findings

    Why it is in this group

    • Nothing in its name or description says what it does, so it is counted as a write.
    • The server marks it read-only (readOnlyHint: true), but an annotation never lowers a class.
    Description, as the server wrote it
    Two charts compared: inter-chart aspects with orbs, house overlays both ways and a score per life sphere. (API Pro) Use it when the user asks about compatibility or a relationship and gives birth data for both people.

    Annotations the server declares

    • title: Synastry (two charts)
    • readOnlyHint: true
    • idempotentHint: true
    • openWorldHint: false
  • usageYour plan, today's count and when the pool refills.No findings

    Why it is in this group

    • Nothing in its name or description says what it does, so it is counted as a write.
    • The server marks it read-only (readOnlyHint: true), but an annotation never lowers a class.
    Description, as the server wrote it
    Your plan, today's count and when the pool refills. Costs nothing. Use it when a call fails on the limit, or before a long series of calls, to see the plan and what is left today.

    Annotations the server declares

    • title: Requests left today
    • readOnlyHint: true
    • idempotentHint: true
    • openWorldHint: false

This is not a safety rating, and no finding is not a safety guarantee. The groups and findings come from fixed checks of the tool definitions the server returned on the date shown, not from its code or what it does when called. How the checks work.

Install

Pinned to version 1.0.0. Values in angle brackets are yours to fill in.

claude mcp add --transport http astrology https://www.natalchart.ai/mcp --header 'Authorization: <your-authorization>'

Run in a terminal.

Claude Code permissions

Allow the reads, ask before a change, deny the deletes. Paste into .claude/settings.json.

.claude/settings.json
{
  "permissions": {
    "allow": [],
    "ask": [
      "mcp__astrology__natal_chart",
      "mcp__astrology__daily_transits",
      "mcp__astrology__sky",
      "mcp__astrology__usage",
      "mcp__astrology__transits",
      "mcp__astrology__synastry",
      "mcp__astrology__solar_return",
      "mcp__astrology__best_days",
      "mcp__astrology__location_score",
      "mcp__astrology__best_cities"
    ],
    "deny": []
  }
}

Tools that only read are allowed, tools that change things ask first, tools that delete or cancel are denied. It assumes the server is installed as astrology. Review it before you use it.