naelos MCP server

None of its 10 tools are described as changing anything. For 10 the reading was uncertain, so no mark is shown.

• natal_charton 7 other servers

  “A complete natal (birth) chart: every planet's sign, degree and house, the Ascendant and Midheaven, retrogrades, and the aspects between planets with exact orbs.”

  Publisher declares: read-only yes · idempotent yes · open-world no

  7 inputs, 4 required

  • datestringrequired“Birth date, YYYY-MM-DD”
  • timestring“Local clock time, HH:MM (24-hour).”
  • latitudenumberrequired“Birthplace latitude in decimal degrees (north positive)”
  • longitudenumberrequired“Birthplace longitude in decimal degrees (east positive)”
  • timezonestringrequired“IANA time zone of the birthplace, e.g.”
  • placestring“Birthplace name, echoed back so the user can check the coordinates”
  • house_systemstring“House system (default placidus)”
• sky_nowon 2 other servers

  “Where every planet is at a moment (now by default): sign, degree, retrograde, and the aspects between them.”

  Publisher declares: read-only yes · idempotent yes · open-world no

  3 inputs

  • datetime_utcstring“The moment in UTC, YYYY-MM-DDTHH:MM (default now)”
  • latitudenumber
  • longitudenumber
• planet_position

  “One body's tropical position on a date, anywhere from 13,200 BC to AD 17,191, with its speed and whether it is retrograde.”

  Publisher declares: read-only yes · idempotent yes · open-world no

  3 inputs, 2 required

  • bodystringrequired
  • datestringrequired
  • time_utcstring“HH:MM UTC (default 12:00)”
• transitson 3 other servers

  “Every exact transit of the planets (Sun to Pluto; the Moon is left out as it aspects everything monthly) to a birth chart's planets, Ascendant and Midheaven over a span, with the exact date of each a…”

  Publisher declares: read-only yes · idempotent yes · open-world no

  8 inputs, 4 required

  • datestringrequired“Birth date, YYYY-MM-DD”
  • timestring“Local clock time, HH:MM (24-hour).”
  • latitudenumberrequired“Birthplace latitude in decimal degrees (north positive)”
  • longitudenumberrequired“Birthplace longitude in decimal degrees (east positive)”
  • timezonestringrequired“IANA time zone of the birthplace, e.g.”
  • placestring“Birthplace name, echoed back so the user can check the coordinates”
  • fromstring“Start date (default today)”
  • daysinteger“Length of the span in days (default 30, at most 366)”
• synastryon 2 other servers

  “The aspects between two people's birth charts (each one's planets to the other's), with exact orbs and strength.”

  Publisher declares: read-only yes · idempotent yes · open-world no

  2 inputs, 2 required

  • person_aobjectrequired“First person's birth data”
  • person_bobjectrequired“Second person's birth data”
• returnson 1 other server

  “The solar return for a year (the moment the Sun returns to its birth position, the chart for that year) or the lunar return nearest now, cast for the birthplace or another location.”

  Publisher declares: read-only yes · idempotent yes · open-world no

  10 inputs, 5 required

  • datestringrequired“Birth date, YYYY-MM-DD”
  • timestring“Local clock time, HH:MM (24-hour).”
  • latitudenumberrequired“Birthplace latitude in decimal degrees (north positive)”
  • longitudenumberrequired“Birthplace longitude in decimal degrees (east positive)”
  • timezonestringrequired“IANA time zone of the birthplace, e.g.”
  • placestring“Birthplace name, echoed back so the user can check the coordinates”
  • kindstringrequired
  • yearinteger“Solar return year (default this year)”
  • return_latitudenumber“Where the person is for the return, if not the birthplace”
  • return_longitudenumber
• progressionson 1 other server

  “The progressed chart as of today: secondary progressions (a day after birth for each year of life) or solar arc directions (every point moved by the Sun's progressed arc).”

  Publisher declares: read-only yes · idempotent yes · open-world no

  7 inputs, 4 required

  • datestringrequired“Birth date, YYYY-MM-DD”
  • timestring“Local clock time, HH:MM (24-hour).”
  • latitudenumberrequired“Birthplace latitude in decimal degrees (north positive)”
  • longitudenumberrequired“Birthplace longitude in decimal degrees (east positive)”
  • timezonestringrequired“IANA time zone of the birthplace, e.g.”
  • placestring“Birthplace name, echoed back so the user can check the coordinates”
  • methodstring“Default secondary”
• timing_events

  “Between two dates: planets changing sign, new and full Moons (and quarters), and retrograde and direct stations, each with its exact moment in UTC.”

  Publisher declares: read-only yes · idempotent yes · open-world no

  3 inputs, 2 required

  • fromstringrequired
  • tostringrequired
  • kindsarray“Default all three”
• eclipses

  “Solar and lunar eclipses between two dates (up to 20 years per call), with type, the exact moment of greatest eclipse and the eclipse degree.”

  Publisher declares: read-only yes · idempotent yes · open-world no

  2 inputs, 2 required

  • fromstringrequired
  • tostringrequired
• naelos_library

  “Which national charts (198) and empire charts (19) Naelos holds, each researched and sourced, with the founding event it is cast for.”

  Publisher declares: read-only yes · idempotent yes · open-world no

  1 input

  • searchstring“Filter by name, e.g.”

Each quoted sentence is the first sentence of the publisher’s own description. The kind of tool and the “changes data” mark are our AI model’s reading of that description, not something we tested: two differently worded runs had to agree, otherwise no label is shown, and nobody has checked them by hand. A tool without the “changes data” mark is described as only reading, searching or calculating, or the two runs did not agree. No tool was called. Read the publisher’s full description before relying on it. “Publisher declares” lists the hints the server itself sends with the tool (MCP annotations: read-only, destructive, idempotent, open-world); they are the publisher's claims, not checked by us. Inputs are the parameters in the tool's own input schema: name, declared type, whether it is required, and the first sentence of its description. Read 2026-10-29.

The registry checks an entry when it is published (each new version), and nothing re-checks it on a schedule. A difference below is about the listing, not a judgement of the publisher.