diff --git a/.claude/skills/discord-supporter/README.md b/.claude/skills/discord-supporter/README.md
new file mode 100644
index 00000000..3fc9a64a
--- /dev/null
+++ b/.claude/skills/discord-supporter/README.md
@@ -0,0 +1,61 @@
+# discord-supporter
+
+This directory is a Claude Code skill for semi-automatic support on the
+OpenArm Discord. `SKILL.md` is the procedure that Claude Code follows.
+This file is for humans who set up the bot.
+
+## Set up the bot
+
+1. Create an application in the
+   [Discord Developer Portal](https://discord.com/developers/applications).
+2. Open **Bot**:
+   - Click **Reset Token** and copy the token. It is shown only once.
+   - Enable **Message Content Intent**. Without it, the scripts get
+     messages with empty content.
+3. Open **OAuth2 → URL Generator**, select the `bot` scope and the
+   following permissions, and open the generated URL to invite the bot to
+   the server:
+   - View Channels
+   - Read Message History
+   - Send Messages
+   - Send Messages in Threads
+
+The permissions are kept in the role that Discord creates for the bot.
+You can change them later in **Server Settings → Roles** without inviting
+the bot again.
+
+## Set the token
+
+Set the token in `DISCORD_TOKEN`. Claude Code starts a new shell for each
+command, so `export` in a command doesn't persist. Set it in your shell
+startup file such as `~/.zshenv`, or set it before starting Claude Code:
+
+```sh
+export DISCORD_TOKEN=...
+```
+
+Keep the token secret. Don't commit it or paste it into a conversation. If
+it leaks, reset it in the Developer Portal.
+
+## Environment variables
+
+| Variable | Description | Default |
+|---|---|---|
+| `DISCORD_TOKEN` | Bot token | (required) |
+| `DISCORD_GUILD_ID` | Server ID | `1339899404546740275` (OpenArm) |
+| `DISCORD_SUPPORTER_STATE` | Path of the state file | `state.json` in this directory |
+
+## Check the setup
+
+List the channels that the scripts scan:
+
+```sh
+python3 .claude/skills/discord-supporter/scripts/discord_fetch.py --channels
+```
+
+The scripts scan only public channels, which the `@everyone` role can
+view. When you add a channel, make sure that it is listed, and run
+`discord_fetch.py` without options. If the bot can't view a listed
+channel because of the category or channel permissions, it fails with
+`Discord API error 403`. Allow the bot role to view the channel in that
+case.
diff --git a/.claude/skills/discord-supporter/scripts/discord_api.py b/.claude/skills/discord-supporter/scripts/discord_api.py
index 86a0ccc7..d002d11c 100644
--- a/.claude/skills/discord-supporter/scripts/discord_api.py
+++ b/.claude/skills/discord-supporter/scripts/discord_api.py
@@ -35,7 +35,10 @@
 def token():
     value = os.environ.get("DISCORD_TOKEN")
     if not value:
-        sys.exit("DISCORD_TOKEN is not set")
+        sys.exit(
+            "DISCORD_TOKEN is not set "
+            "(see .claude/skills/discord-supporter/README.md)"
+        )
     return value