CronSpell
Validate and explain cron expressions; list next/previous run times in any time zone, DST-aware.
What it does
CronSpell is an MCP server, a connector that lets an AI assistant use it as a tool. It is hosted: an assistant connects to it over the internet, nothing to install.
No capability identified yet from its description.
Facts come from the Official MCP Registry, as declared by the publisher. Capabilities are matched automatically (low confidence) and are not a test of the tool.
At a glance
How to connect
As declared in the Official MCP Registry · hosted endpoint tested by Electra Index 1h ago (live check)Hosted endpoint
https://cronspell.mike-tusa.workers.dev/mcpstreamable-http
In Claude Code: claude mcp add --transport http cronspell https://cronspell.mike-tusa.workers.dev/mcp
MCP settings (Claude Desktop, Cursor and other MCP clients)
{
"mcpServers": {
"cronspell": {
"url": "https://cronspell.mike-tusa.workers.dev/mcp"
}
}
}Live check
Electra Index connected to the hosted endpoint 1h agoONLINE CronSpell answered an MCP connection on 22 Oct 2026 and introduced itself as cronspell 0.1.0 (MCP protocol 2025-06-18).
4 tools offered to AI assistants
validate_cron· Check whether a cron expression is valid. Returns valid true with the expanded values of every field (minute, hour, day of month, month, day of week, and seconds for 6-field expressions), or valid false with an error code, the field at faulexplain_cron· Explain a cron expression in plain English, e.g. "0 9 * * 1-5" → "At 09:00, on Monday through Friday." Also returns notes on cron rules that often surprise people (day-of-month OR day-of-week, seconds field, shorthand expansion). Invalid exnext_cron_runs· List the next (or, with direction "previous", the most recent past) run times of a cron expression in an IANA time zone, DST-aware. Each run has the local time with its UTC offset, the UTC time, unix seconds and weekday. Default 5 runs, maxcron_runs_between· List every run of a cron expression between start and end (both inclusive) in an IANA time zone, DST-aware, oldest first. Default limit 20, max 100; truncated is true when there are more. Read-only. Same engine as GET /api/between.
What "online" means: the server answered an MCP connection at the time of the check. It is not a guarantee of security, quality or continuous uptime. How we test: we open an MCP session and ask for the tool list, as an AI assistant would. We never run a tool and never send a key. Checked every few days. Method
Facts & evidence
Each fact shows where it was seen and when.| Fact | Value | Evidence | Source | Last confirmed |
|---|---|---|---|---|
| Hosted endpoint | https://cronspell.mike-tusa.workers.dev/mcp | DECLARED | SRC-001 Official MCP Registry | 1h ago |
| Local install (package) | no | DECLARED | SRC-001 Official MCP Registry | 1h ago |
| Remote access (hosted) | yes | DECLARED | SRC-001 Official MCP Registry | 1h ago |
| Website | https://cronspell.mike-tusa.workers.dev/ | DECLARED | SRC-001 Official MCP Registry | 1h ago |
| Registry status | active | DECLARED | SRC-001 Official MCP Registry | 1h ago |
| Version | 0.1.0 | DECLARED | SRC-001 Official MCP Registry | 1h ago |
| MCP server | yes | DECLARED | SRC-001 Official MCP Registry | 1h ago |
Change history
- NEW22 Oct 2026first seen in the index
Is this page accurate?
Flag it and our robot re-checks the official source. Reports never change a score.Is CronSpell still online?
Free alerts · no accountQuestions about CronSpell
How do I connect CronSpell?
Use the hosted endpoint https://cronspell.mike-tusa.workers.dev/mcp in your assistant's MCP settings. The exact settings are in "How to connect" above, as declared in the Official MCP Registry.
What tools does CronSpell offer?
When Electra Index connected on 22 Oct 2026, it listed 4 tools: validate_cron, explain_cron, next_cron_runs, cron_runs_between. The full list is in "Live check" above.
Is CronSpell online?
Yes. Its hosted endpoint answered an MCP connection from Electra Index 1h ago.