pi-time-inject

Time injection for pi: stamps every user message with the real current time, so the model always sees an accurate "now". This is a port of the Claude Code UserPromptSubmit date hook — needed because third-party models like GLM/DeepSeek have no built-in clock, and a missing date once caused a calver week miscalculation.

[消息提交时间 2026-08-25 Tuesday 08:32:44 GMT+8 —— 以最新一条为当前时间]

Table of Contents

• Features
• Requirements
• Installation
• How It Works
• Development
• Troubleshooting
• License

Features

• Per-message stamps, never a global "now": each user message's stamp is derived from its own creation timestamp (epoch ms), so a message carries the identical stamp on every request — within a tool loop, across turns, across restarts, and for unbounded history. Deterministic and stateless: no mutable state, no concurrency issues.
• Prefix-cache friendly: the stamp is appended to the END of user messages, never to the system prompt. DeepSeek-style context caches match requests byte-for-byte from token 0 — a per-turn stamp in the system prompt would break the match and re-bill the ENTIRE history at full price every turn. With user-message appends, the changing part sits at the very end of the sequence and the system prompt + history stay cache-hit.
• Session stays clean: the context event transforms are request-time only — the session file, /undo, exports and other extensions never see the stamp.
• No input-transform pollution: rewriting user text in the input event would leak the stamp into other extensions' prompt capture (e.g. notify extensions), so the stamp is applied in context instead.
• Fail-open: any failure logs rate-limited (max one line per 5 minutes per channel) and returns the original messages untouched. Never throws, never blocks the agent loop. A single malformed message isolates itself — it skips only itself, the rest still get stamps.

Requirements

• pi ≥ 0.84 (uses the context event). No other dependencies.

Installation

From npm (recommended)

pi install npm:@zhuxixi/pi-time-inject

Then run /reload in pi (no restart needed).

To update later:

pi update --extensions

To remove:

pi remove npm:@zhuxixi/pi-time-inject

From source

Clone the repository into a subdirectory of pi's global extensions dir:

git clone https://github.com/zhuxixi/pi-time-inject.git ~/.pi/agent/extensions/pi-time-inject

How It Works

1. On the context event (fires before every LLM call with a structured-clone'd messages array), the extension walks the user messages and appends a stamp line to each.
2. The stamp wording is position-neutral and byte-identical for every message — [消息提交时间 YYYY-MM-DD Weekday HH:MM:SS TZ —— 以最新一条为当前时间] — so a message's stamp never changes as it ages from latest to history (that would break the cache prefix at that message).
3. The timezone abbreviation comes from Intl.DateTimeFormat (may render as GMT+8 rather than Claude Code's CST) — equally unambiguous to the model, and avoids forking a date subprocess per prompt.
4. Failures are rate-limited-logged per channel (error vs skip) and never thrown. The skip channel reports stamped X/Y user messages when any user message is skipped.

No configuration, no commands, no state files — it just works.

Development

./test/run-all.sh   # bundles test/*.test.ts with esbuild and runs them

Tests are dependency-free: lib/inject-stamp.ts is pure and tested directly, index.ts (the handler layer) is tested through a minimal ExtensionAPI stub covering the catch contract, return shapes and rate-limited logging.

After editing, run /reload inside pi to hot-reload the extension.

Troubleshooting

• No stamps appear: check that the extension is listed in pi config; after install you must /reload (or restart) pi for the extension to load.
• Some messages lack stamps: a malformed message (non-number timestamp, unknown content shape) skips only itself — check stderr for a rate-limited [time-inject] stamped X/Y user messages line.
• Stamp timezone looks wrong: the abbreviation comes from the system locale's Intl data; the epoch itself is the message's own creation time, which is what matters for correctness.

License

MIT