feat(cron): expand to 20 fires/day, packed into 5 expressions

CHANGELOG.md

@@ -11,7 +11,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ### Added
 - Cloudflare Workers `scheduled` handler that POSTs to the Claude Code routine `/fire` endpoint.
-- Default 5×daily cron at UTC+7 (00:07 / 05:13 / 10:19 / 15:23 / 20:37) — scattered minutes for shared-infra hygiene.
+- Default 20×daily cron at UTC+7 — 00:00 once, then hourly 05-09 / 10-14 / 15-19 / 20-23 with stepped minute offsets (:01-:04). Packed into 5 cron expressions to fit the CF free-tier limit.
 - Token-substitution template with `{ISO}`, `{LocalTime}`, `{Cron}` (default: `Scheduled trigger at {LocalTime}`).
 - IANA timezone support via `TZ` env var (default: `UTC`).
 - Structured JSON logs for fire success / non-2xx / network failure.

README.md

@@ -60,9 +60,11 @@ Edit `wrangler.toml` `[triggers].crons` — Cloudflare requires literal cron exp
 ```toml
 [triggers]
 crons = [
-  "7 17 * * *",   # 00:07 UTC+7
-  "13 22 * * *",  # 05:13 UTC+7
-  # add / remove / edit these lines as needed
+  "0 17 * * *",          # 00:00 UTC+7  (17:00 UTC prev day)
+  "1 22,23,0,1,2 * * *", # 05:01-09:01 UTC+7
+  "2 3-7 * * *",         # 10:02-14:02 UTC+7
+  "3 8-12 * * *",        # 15:03-19:03 UTC+7
+  "4 13-16 * * *",       # 20:04-23:04 UTC+7
 ]
 ```
 
@@ -71,8 +73,8 @@ Then redeploy: `npx wrangler deploy`.
 Tips:
 - Cron runs in **UTC**. Convert your local time: `UTC = local − offset` (e.g. 09:00 UTC+7 → 02:00 UTC → `0 2 * * *`).
 - Validate expressions at <https://crontab.guru/>.
-- **Free tier limit:** 5 cron expressions per worker. Default config uses all 5. To run more schedules, deploy another worker.
-- Scattering minutes (e.g. `7`, `13`, `19`, `23`, `37`) is good hygiene on shared infrastructure even though CF cron is more reliable than GitHub.
+- **Free tier limit:** 5 cron expressions per worker. Default config uses all 5. Use comma lists (`1 22,23,0,1,2 * * *`) and ranges (`2 3-7 * * *`) to fit more fires per row.
+- Standard 5-field syntax — supports `*`, `,`, `-`, `/`. Use minute offsets (`:01`, `:02`, …) instead of `:00` to avoid top-of-hour contention on shared infra.
 
 ## Templates
 

wrangler.toml

@@ -11,17 +11,22 @@ TZ = "Asia/Ho_Chi_Minh"
 
 # Cron triggers fire from this list. CF Workers requires literal cron
 # expressions here — they cannot be loaded from env vars or secrets.
-# Default schedule mirrors the sibling repos: 5x daily at UTC+7
-# 00:07 / 05:13 / 10:19 / 15:23 / 20:37 — minutes scattered to avoid
-# top-of-hour contention (good hygiene; CF cron is more reliable than GH).
+# Schedule (Asia/Ho_Chi_Minh, UTC+7) — 20 fires/day, packed into 5 expressions:
+#   00:00         — once at local midnight
+#   05:01-09:01   — every hour, minute 01
+#   10:02-14:02   — every hour, minute 02
+#   15:03-19:03   — every hour, minute 03
+#   20:04-23:04   — every hour, minute 04
+# Crons evaluate in UTC, so each row is offset by -7 hours; the 05-09 row
+# wraps midnight UTC so it uses a comma list rather than a range.
 # Free tier allows up to 5 cron expressions per worker — at limit.
 [triggers]
 crons = [
-  "7 17 * * *",
-  "13 22 * * *",
-  "19 3 * * *",
-  "23 8 * * *",
-  "37 13 * * *",
+  "0 17 * * *",          # 00:00 UTC+7  (17:00 UTC prev day)
+  "1 22,23,0,1,2 * * *", # 05:01-09:01 UTC+7
+  "2 3-7 * * *",         # 10:02-14:02 UTC+7
+  "3 8-12 * * *",        # 15:03-19:03 UTC+7
+  "4 13-16 * * *",       # 20:04-23:04 UTC+7
 ]
 
 # Built-in observability (free tier supports basic logs).