docs: document DM history limits (#883)

Thanks @pkrmf.

Co-authored-by: Marc Terns <tenxurz@gmail.com>

docs/channels/discord.md

@@ -300,6 +300,7 @@ ack reaction after the bot replies.
 - `maxLinesPerMessage`: soft max line count per message. Default: 17.
 - `mediaMaxMb`: clamp inbound media saved to disk.
 - `historyLimit`: number of recent guild messages to include as context when replying to a mention (default 20; falls back to `messages.groupChat.historyLimit`; `0` disables).
+- `dmHistoryLimit`: DM history limit in user turns. Per-user overrides: `dms["<user_id>"].historyLimit`.
 - `retry`: retry policy for outbound Discord API calls (attempts, minDelayMs, maxDelayMs, jitter).
 - `actions`: per-action tool gates; omit to allow all (set `false` to disable).
   - `reactions` (covers react + read reactions)

docs/channels/imessage.md

@@ -189,6 +189,7 @@ Provider options:
 - `channels.imessage.groupPolicy`: `open | allowlist | disabled` (default: allowlist).
 - `channels.imessage.groupAllowFrom`: group sender allowlist.
 - `channels.imessage.historyLimit` / `channels.imessage.accounts.*.historyLimit`: max group messages to include as context (0 disables).
+- `channels.imessage.dmHistoryLimit`: DM history limit in user turns. Per-user overrides: `channels.imessage.dms["<handle>"].historyLimit`.
 - `channels.imessage.groups`: per-group defaults + allowlist (use `"*"` for global defaults).
 - `channels.imessage.includeAttachments`: ingest attachments into context.
 - `channels.imessage.mediaMaxMb`: inbound/outbound media cap (MB).

docs/channels/msteams.md

@@ -208,6 +208,7 @@ This is often easier than hand-editing JSON manifests.
 ## History context
 - `channels.msteams.historyLimit` controls how many recent channel/group messages are wrapped into the prompt.
 - Falls back to `messages.groupChat.historyLimit`. Set `0` to disable (default 50).
+- DM history can be limited with `channels.msteams.dmHistoryLimit` (user turns). Per-user overrides: `channels.msteams.dms["<user_id>"].historyLimit`.
 
 ## Current Teams RSC Permissions (Manifest)
 These are the **existing resourceSpecific permissions** in our Teams app manifest. They only apply inside the team/chat where the app is installed.

docs/channels/signal.md

@@ -124,6 +124,7 @@ Provider options:
 - `channels.signal.groupPolicy`: `open | allowlist | disabled` (default: allowlist).
 - `channels.signal.groupAllowFrom`: group sender allowlist.
 - `channels.signal.historyLimit`: max group messages to include as context (0 disables).
+- `channels.signal.dmHistoryLimit`: DM history limit in user turns. Per-user overrides: `channels.signal.dms["<phone_or_uuid>"].historyLimit`.
 - `channels.signal.textChunkLimit`: outbound chunk size (chars).
 - `channels.signal.mediaMaxMb`: inbound/outbound media cap (MB).
 

docs/channels/slack.md

@@ -66,6 +66,7 @@ Or via config:
 ## History context
 - `channels.slack.historyLimit` (or `channels.slack.accounts.*.historyLimit`) controls how many recent channel/group messages are wrapped into the prompt.
 - Falls back to `messages.groupChat.historyLimit`. Set `0` to disable (default 50).
+- DM history can be limited with `channels.slack.dmHistoryLimit` (user turns). Per-user overrides: `channels.slack.dms["<user_id>"].historyLimit`.
 
 ## Config writes
 By default, Slack is allowed to write config updates triggered by channel events or `/config set|unset`.

docs/channels/telegram.md

@@ -105,6 +105,7 @@ group messages, so use admin if you need full visibility.
 - Media downloads/uploads are capped by `channels.telegram.mediaMaxMb` (default 5).
 - Telegram Bot API requests time out after `channels.telegram.timeoutSeconds` (default 500 via grammY). Set lower to avoid long hangs.
 - Group history context uses `channels.telegram.historyLimit` (or `channels.telegram.accounts.*.historyLimit`), falling back to `messages.groupChat.historyLimit`. Set `0` to disable (default 50).
+- DM history can be limited with `channels.telegram.dmHistoryLimit` (user turns). Per-user overrides: `channels.telegram.dms["<user_id>"].historyLimit`.
 
 ## Group activation modes
 

docs/channels/whatsapp.md

@@ -292,6 +292,7 @@ WhatsApp can automatically send emoji reactions to incoming messages immediately
 - `channels.whatsapp.groupAllowFrom` (group sender allowlist).
 - `channels.whatsapp.groupPolicy` (group policy).
 - `channels.whatsapp.historyLimit` / `channels.whatsapp.accounts.<accountId>.historyLimit` (group history context; `0` disables).
+- `channels.whatsapp.dmHistoryLimit` (DM history limit in user turns). Per-user overrides: `channels.whatsapp.dms["<phone>"].historyLimit`.
 - `channels.whatsapp.groups` (group allowlist + mention gating defaults; use `"*"` to allow all)
 - `channels.whatsapp.actions.reactions` (gate WhatsApp tool reactions).
 - `agents.list[].groupChat.mentionPatterns` (or `messages.groupChat.mentionPatterns`)