Sync Day is a remote MCP server that gives an AI agent 8 tools, among them create_event, decide_time, get_event. It answers at https://sync.day/mcp/mcp over streamable HTTP, and it listed its tools to an anonymous client, so no sign-in was needed for that. Our probes reached it 6 of 6 times since 11 September 2026; the last check, on 24 October 2026, succeeded.
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Description as the publisher wrote it.
| Tool | What it does |
|---|---|
create_event | Create a sync.day availability poll and get its share link. Candidate days run from startDate to endDate (inclusive; or give days instead). Each day offers candidate START times from hourFrom, every startStepMinutes, as long as start + dura Inputs: title, question, startDate, endDate, days, hourFrom |
decide_time | Organiser only: settle on a start time (locks availability picking and voting; the page shows 已定). Pass start=null to reopen. Requires the adminKey from create_event. Inputs: slug, adminKey, start |
get_event | Read an event: settings, every candidate start key per day (startOptions), who has answered (participants with their start keys; names may repeat), the top 10 start times by head-count (ranked), the starts EVERYONE with picks can make with Inputs: slug |
parse_event_text | Turn a natural-language sentence (Chinese works best) into create_event input using sync.day's AI parser. Does NOT create anything; review the result, then call create_event. Example: '下周六或周日下午聚餐，大概 3 小时'. Inputs: text, today |
remove_participant | Organiser only: remove one participant by name (the oldest row with that name when it repeats), together with their vote. Requires the adminKey from create_event. Inputs: slug, name, adminKey |
submit_availability | Save (or replace) one person's availability: the candidate start keys they can make, from get_event.startOptions. The person is identified by `identity`, not by name: the same identity later overwrites the same row (and can rename it), a di Inputs: slug, identity, name, starts |
update_event | Organiser only: change any event settings (same fields and rules as create_event; omitted fields keep their current value; endDate wins over days). Existing picks are kept; those no longer valid starts are just hidden. Inputs: slug, adminKey, title, question, startDate, endDate |
vote_time | Approval voting: set every start one person accepts (replaces their earlier approvals; an empty list clears them). The voter is the `identity` used in submit_availability and must have at least one start saved. Only keys listed in get_event Inputs: slug, identity, starts, start |
Every block below points at https://sync.day/mcp/mcp. Pick your client and copy.
claude mcp add --transport http sync-day https://sync.day/mcp/mcp
{
"mcpServers": {
"sync-day": {
"command": "npx",
"args": ["-y", "mcp-remote", "https://sync.day/mcp/mcp"]
}
}
}{
"mcpServers": {
"sync-day": {
"url": "https://sync.day/mcp/mcp"
}
}
}{
"servers": {
"sync-day": {
"type": "http",
"url": "https://sync.day/mcp/mcp"
}
}
}{
"context_servers": {
"sync-day": {
"url": "https://sync.day/mcp/mcp"
}
}
}{
"mcpServers": {
"sync-day": {
"serverUrl": "https://sync.day/mcp/mcp"
}
}
}{
"mcpServers": {
"sync-day": {
"url": "https://sync.day/mcp/mcp"
}
}
}name: Sync Day
version: 0.0.1
schema: v1
mcpServers:
- name: Sync Day
type: streamable-http
url: https://sync.day/mcp/mcp{
"mcpServers": {
"sync-day": {
"httpUrl": "https://sync.day/mcp/mcp"
}
}
}{
"mcpServers": {
"sync-day": {
"type": "http",
"url": "https://sync.day/mcp/mcp"
}
}
}{
"mcpServers": {
"sync-day": {
"url": "https://sync.day/mcp/mcp"
}
}
}goose://extension?url=https%3A%2F%2Fsync.day%2Fmcp%2Fmcp&type=streamable_http&id=sync-day&name=Sync%20Day
It answered our last check on 24 October 2026 in 637 ms. Over 6 checks since 11 September 2026 it answered 6. Status here comes from Neuronto's own probes, not from the publisher.
8, as returned by the server's own tools/list on 21 September 2026: create_event, decide_time, get_event, parse_event_text, remove_participant, submit_availability, update_event, vote_time.
It answered our last check on 24 October 2026 in 637 ms. Over 6 checks since 11 September 2026 it answered 6.
Put the server under mcpServers in ~/.cursor/mcp.json with the URL https://sync.day/mcp/mcp. The exact JSON is above, with the same setup for Claude Code, Claude Desktop, VS Code, Windsurf, Zed, Gemini CLI and the rest.
It listed its tools to an anonymous client, so reading the tool list needs no key. Individual tools can still ask for credentials in their own inputs.
Publisher: io.github.syncday-app. Endpoint host: sync.day. ARD identifier: urn:air:io.github.syncday-app:mcp:sync-day.
First indexed 10 September 2026. The tools are exactly what the server returned; nothing on this page
is inferred from its name. Ranking in Neuronto search is never for sale.