Discord threads and sessions

Forum threads, history and context limits, subagent thread sessions, and ACP channel bindings

How Discord threads, forums, and channels map onto OpenClaw sessions.

Forum channels

Discord forum and media channels only accept thread posts. OpenClaw supports two ways to create them:

Send a message to the forum parent (channel:<forumId>) to auto-create a thread. The thread title is the first non-empty line of the message (truncated to Discord's 100-character thread-name limit).
Use openclaw message thread create to create a thread directly. Do not pass --message-id for forum channels.

Send to the forum parent to create a thread:

openclaw message send --channel discord --target channel:<forumId> \
  --message "Topic title\nBody of the post"

Create a forum thread explicitly:

openclaw message thread create --channel discord --target channel:<forumId> \
  --thread-name "Topic title" --message "Body of the post"

Forum parents do not accept Discord components. If you need components, send to the thread itself (channel:<threadId>).

When thread-create successfully sends all initial content, its result reports confirmed message IDs and chunk counts in initialMessageDelivery with status: "delivered". threadSnapshot: "creation" means the returned thread fields describe creation time; do not retry content based on message_count or last_message_id. Empty standalone threads have no initial-delivery receipt. Partial failures report accepted chunks separately; failedChunkDelivery: "unknown" means the failed chunk may have been delivered, so inspect the thread before retrying.

Session and thread behavior

History, context, and thread behavior

Guild history context:

channels.discord.historyLimit default 20
fallback: messages.groupChat.historyLimit
0 disables automatic guild/thread history reads, not explicit message reads or reply context.

Admitted guild turns fetch their recent window from Discord, including after Gateway restart. Thread turns use the exact thread channel, not its parent. Unmentioned messages in mention-gated rooms remain quiet. Current and batched source messages, later messages, and rows before the active session boundary are excluded. Sender visibility still applies; filtering can yield fewer messages than the configured limit. Other bots' messages remain available as context even when allowBots: false disables their ability to trigger turns. The receiving bot's own output is excluded from automatic history.

Human replies carry the selected parent message independently of allowBots. Missing or empty nested reply payloads are fetched from Discord. If the parent is deleted or unavailable, its reply ID remains in context rather than silently turning the message into an unrelated top-level question. contextVisibility still controls which supplemental reply content is included.

Discord owns the history: fresh reads reflect its current message content, deletions, permissions, and availability. No separate durable message archive is created. If automatic recovery fails, OpenClaw logs the omission and continues the addressed turn. Historical attachments without reusable local media are marked unavailable instead of restoring stale media. Recovery does not rewrite prior agent transcripts.

The existing message(action="read") tool keeps native pagination and exact message lookup. Older reads remain available after restart or /new, subject to Discord's Read Message History permission and current access rules.

DM history controls:

channels.discord.dmHistoryLimit
channels.discord.dms["<user_id>"].historyLimit

Thread behavior:

Discord threads route as channel sessions and inherit parent channel config unless overridden.
Thread sessions inherit the parent channel's session-level /model selection as a model-only fallback; thread-local /model selections take precedence, and parent transcript history is not copied unless transcript inheritance is enabled.
channels.discord.thread.inheritParent (default false) opts new auto-threads into seeding from the parent transcript. Per-account override: channels.discord.accounts.<id>.thread.inheritParent.
Message-tool reactions can resolve user:<id> DM targets.
guilds.<guild>.channels.<channel>.requireMention: false is preserved during reply-stage activation fallback.

Channel topics are injected as untrusted context. Allowlists gate who can trigger the agent, not a full supplemental-context redaction boundary.

Thread-bound sessions for subagents

Discord can bind a thread to a session target so follow-up messages in that thread keep routing to the same session (including subagent sessions).

Commands:

- `/session unbind` remove the current thread binding without closing its agent session
- `/agents` show active runs and binding state
- `/session idle <duration|off>` inspect/update inactivity expiry for the current binding
- `/session max-age <duration|off>` inspect/update hard max age for the current binding

Config:

{
  session: {
    threadBindings: {
      enabled: true,
      idleHours: 24,
      maxAgeHours: 0,
      spawnSessions: true,
      defaultSpawnContext: "fork",
    },
  },
}

Notes:

- `session.threadBindings.*` is the canonical policy for Discord and Telegram.
- `spawnSessions` controls auto-create/bind threads for `sessions_spawn({ thread: true })` and ACP thread spawns. Default: `true`.
- `defaultSpawnContext` controls native subagent context for thread-bound spawns. Default: `"fork"`.
- Deprecated `spawnSubagentSessions`/`spawnAcpSessions` keys are migrated by `openclaw doctor --fix`.
- If thread bindings are disabled, thread-bound spawns are unavailable.

See [Sub-agents](/agents/openclaw/tools/subagents/), [ACP Agents](/agents/openclaw/tools/acp-agents/), and [Configuration Reference](/agents/openclaw/gateway/configuration-reference/).

Persistent ACP channel bindings

For stable "always-on" ACP workspaces, configure top-level typed ACP bindings targeting Discord conversations.

Config path: `bindings[]` with `type: "acp"` and `match.channel: "discord"`.

{
  agents: {
    entries: {
      codex: {
        runtime: {
          type: "acp",
          acp: {
            agent: "codex",
            backend: "acpx",
            mode: "persistent",
            cwd: "/workspace/openclaw",
          },
        },
      },
    },
  },
  bindings: [
    {
      type: "acp",
      agentId: "codex",
      match: {
        channel: "discord",
        accountId: "default",
        peer: { kind: "channel", id: "222222222222222222" },
      },
      acp: { label: "codex-main" },
    },
  ],
  channels: {
    discord: {
      guilds: {
        "111111111111111111": {
          channels: {
            "222222222222222222": {
              requireMention: false,
            },
          },
        },
      },
    },
  },
}

Notes:

- `/acp spawn codex --bind here` binds the current channel or thread in place and keeps future messages on the same ACP session. Thread messages inherit the parent channel binding.
- In a bound channel or thread, `/new` and `/reset` reset the same ACP session in place. Temporary thread bindings can override target resolution while active.
- `spawnSessions` gates child thread creation/binding via `--thread auto|here`.

See [ACP Agents](/agents/openclaw/tools/acp-agents/) for binding behavior details.