feat(date-time): standardize time context and tool timestamps

docs/concepts/system-prompt.md

@@ -20,7 +20,7 @@ The prompt is intentionally compact and uses fixed sections:
 - **Workspace**: working directory (`agents.defaults.workspace`).
 - **Workspace Files (injected)**: indicates bootstrap files are included below.
 - **Sandbox** (when enabled): indicates sandboxed runtime, sandbox paths, and whether elevated exec is available.
-- **Time**: UTC default + the user’s local time (already converted).
+- **Current Date & Time**: user-local time, timezone, and time format.
 - **Reply Tags**: optional reply tag syntax for supported providers.
 - **Heartbeats**: heartbeat prompt and ack behavior.
 - **Runtime**: host, OS, node, model, thinking level (one line).
@@ -46,12 +46,19 @@ To inspect how much each injected file contributes (raw vs injected, truncation,
 
 ## Time handling
 
-The Time line is compact and explicit:
+The system prompt includes a dedicated **Current Date & Time** section when user
+time or timezone is known. It is explicit about:
 
-- Assume timestamps are **UTC** unless stated.
-- The listed **user time** is already converted to `agents.defaults.userTimezone` (if set).
+- The user’s **local time** (already converted).
+- The **time zone** used for the conversion.
+- The **time format** (12-hour / 24-hour).
 
-Use `agents.defaults.userTimezone` in `~/.clawdbot/clawdbot.json` to change the user time zone.
+Configure with:
+
+- `agents.defaults.userTimezone`
+- `agents.defaults.timeFormat` (`auto` | `12` | `24`)
+
+See [Date & Time](/date-time) for full behavior details.
 
 ## Skills
 

docs/concepts/timezone.md

@@ -19,10 +19,15 @@ Inbound messages are wrapped in an envelope like:
 
 The timestamp in the envelope is **always UTC**, with minutes precision.
 
-## Tool payloads (raw provider data)
+## Tool payloads (raw provider data + normalized fields)
 
 Tool calls (`channels.discord.readMessages`, `channels.slack.readMessages`, etc.) return **raw provider timestamps**.
-These are typically UTC ISO strings (Discord) or UTC epoch strings (Slack). We do not rewrite them.
+We also attach normalized fields for consistency:
+
+- `timestampMs` (UTC epoch milliseconds)
+- `timestampUtc` (ISO 8601 UTC string)
+
+Raw provider fields are preserved.
 
 ## User timezone for the system prompt
 
@@ -31,10 +36,14 @@ unset, Clawdbot resolves the **host timezone at runtime** (no config write).
 
 ```json5
 {
-  agent: { userTimezone: "America/Chicago" }
+  agents: { defaults: { userTimezone: "America/Chicago" } }
 }
 ```
 
 The system prompt includes:
-- `User timezone: America/Chicago`
-- `Current user time: 2026-01-05 15:26`
+- `Current Date & Time` section with local time and timezone
+- `Time format: 12-hour` or `24-hour`
+
+You can control the prompt format with `agents.defaults.timeFormat` (`auto` | `12` | `24`).
+
+See [Date & Time](/date-time) for the full behavior and examples.