opencode-peak-guard

An opencode TUI plugin that intercepts prompt submission during model peak-pricing windows and offers to wait until off-peak.

DeepSeek's official pricing page declares that during peak hours all billing items are charged at 2x the regular price. Peak hours are 09:00-12:00 and 14:00-18:00 Beijing time (UTC+8), applied Monday-Friday only (effective 2026-08-23); weekends are entirely off-peak. There is no API to query the current price tier, so the schedule is computed locally from the clock.

What it does

When you press Enter on the session prompt while the active model's provider is in a peak window, instead of sending immediately you get a choice:

| Option | Behavior | | ------ | -------- | | Send now | Submits the message at the peak (x2) price | | Auto-submit at off-peak | Locks the draft and sends it automatically when the current peak window ends (no keypress needed) | | Wait until off-peak | Keeps your draft; nothing is sent — press Enter again later | | Cancel | Keeps your draft; nothing is sent |

Off-peak, or when the provider is not monitored (e.g. not DeepSeek), Enter behaves exactly as before.

Install

From npm (recommended)

Add the package name to the plugin array in ~/.config/opencode/tui.json and restart opencode — it is installed automatically:

{
  "plugin": ["opencode-peak-guard"]
}

From source (development)

# 1. Clone / symlink the plugin into opencode's plugin directory
mkdir -p ~/.config/opencode/plugins
ln -s /path/to/opencode-peak-guard ~/.config/opencode/plugins/opencode-peak-guard

# 2. Enable it in the TUI config.
# File plugins are referenced by path (a bare name is treated as an npm
# package and would fail to resolve), so use the absolute path:
#   { "plugin": ["oh-my-opencode-slim", "/home/<you>/.config/opencode/plugins/opencode-peak-guard"] }
#
# 3. Restart opencode

Requires opencode >= 1.18 (TUI plugin API, @opencode-ai/plugin).

Verified end-to-end (opencode 1.18.12): with the plugin enabled, pressing Enter on the session prompt during a DeepSeek peak window shows the choice dialog and does not send until you pick an option. Two load-time gotchas were found and fixed during testing — package.json must expose a ./tui export (opencode's entry resolution only looks for exports["./tui"] or a root index file), and the plugin must not rely on TSX/JSX (bun transpiles plugin sources with the CWD's JSX config, which defaults to React; see src/index.ts header for details).

Options

Options are supplied as the plugin entry array in tui.json:

{
  "plugin": [
    ["opencode-peak-guard", {
      "providers": ["deepseek"],
      "windows": [[9, 12], [14, 18]],
      "multiplier": 2,
      "tzOffsetHours": 8,
      "dryRun": false,
      "forceKey": "ctrl+o"
    }]
  ]
}

| Option | Default | Description | | ------ | ------- | ----------- | | providers | ["deepseek"] | Provider IDs subject to peak pricing (case-insensitive) | | windows | [[9,12],[14,18]] | Peak windows [startHour, endHour] in schedule time | | multiplier | 2 | Peak price multiplier (display only) | | tzOffsetHours | 8 | UTC offset of the schedule clock (Beijing = 8) | | dryRun | false | Never block: always send, but show a toast when peak pricing is active | | forceKey | unset | Extra keybinding that force-sends the draft, bypassing the gate | | weekendOffPeak | true | Weekends are all off-peak; set false to apply the windows every day |

Note: DeepSeek's peak/off-peak rule applies Monday-Friday only and took effect 2026-08-23; weekends never gate (gate only triggers on a weekday inside a configured window).

How it works (verified against opencode 1.18.x source)

1. The plugin registers the session_prompt TUI slot and re-renders the host's own Prompt component (identical UI) while capturing its TuiPromptRef.
2. Enter is intercepted with a key intercept hook (api.keymap.intercept, priority above the host default) instead of a keymap binding. A binding unconditionally consumes the key once it matches — which shadows the host's own return → "confirm permission" binding (default priority 0) and breaks Enter-to-confirm on permission/question prompts. The hook decides per keypress: it consumes the key only when the session prompt is focused, no permission/question gate is pending, and the provider is inside a peak window; otherwise it passes the key through so the host handles it natively (submit the prompt, confirm a permission, etc.).
3. The handler checks: dialog open? → skip; prompt focused? → otherwise pass through; provider in providers? time in a peak window? → open the choice dialog via api.ui.dialog; Send now calls TuiPromptRef.submit(), Auto-submit at off-peak registers a timer for the window end that later submits the draft (see below), Wait/Cancel keep the draft untouched.
4. While any modal dialog is open the dialog guard makes the hook pass Enter through to the host, so dialogs keep their own Enter handling.

The auto-submit timer fires at the exact end of the current peak window and then submits only if it is still safe and meaningful: the same session is active, the draft is non-empty, and no modal dialog or host gate (pending permission/question) blocks submission — blocked attempts retry for about a minute before giving up with a toast. Any real submission (including a manual Enter before the window ends, or the forceKey) cancels the pending timer, so a draft is never sent twice.

While a lock is pending, pressing Enter never submits: it re-opens the choice dialog (titled with the pending release time) so you can reschedule, send now, or cancel. The draft stays visible and editable until it is sent — the lock covers submission, not typing (the TUI slot API cannot render-lock the host's prompt from a plugin).

See docs/FEASIBILITY.md for the full research behind this design.

Development

bun install
bun test          # schedule logic unit tests
bunx tsc --noEmit # typecheck

Limitations

• Peak windows are a local time-table; they follow official announcements (configurable via windows).
• Home-route prompt submission is not gated (session prompt only).
• Enter on a non-editor, non-dialog focus target while in base mode is consumed by the plugin and not re-dispatched (rare; documented in the source).
• Auto-submit fires only while opencode stays running: if the process exits before the peak window ends, the draft simply stays in the input box.
• While an auto-submit lock is pending, the draft remains editable (the lock blocks submission, not typing).

License

MIT