paperclip-plugin-slack

Slack Chat OS plugin for Paperclip. Turns Slack into a bidirectional agent command center - notifications, approvals, multi-agent threads, voice-to-task pipelines, custom workflow commands, and proactive agent suggestions.

Built on the Paperclip plugin SDK and the domain event bridge (PR #909).

Why this exists

Multiple Paperclip users asked for notifications on the same day the plugin system shipped (2026-03-14):

"is there a way to have codex/claude check paperclip to see when tasks are done without me prompting it?" - @Choose Liberty, Discord #dev

"basically to have it 'let me know when its done'" - @Choose Liberty, Discord #dev

"can claude code check paperclip to see when tasks are done" - @Nascozz, Discord #dev

@dotta (maintainer) responded: "we're also adding issue-changed hooks for plugins so when that lands someone could [make notifications]." The event bridge (PR #909) shipped that same day. @dotta also asked for "someone to make a plugin that's a totally separate package" to validate the DX. @Ryze said "Really excited by the plugins. I had developed a custom plugin bridge that I will now deprecate and migrate over to the new supported plugin system."

This is that plugin.

What it does

Phase 1: Notifications + HITL Escalation

Notifications (rich Block Kit formatting)

• Issue created - Title, description snippet, status, priority, assignee, project fields, and a "View Issue" button
• Issue done - Completion confirmation with status fields and view button
• Approval requested - Interactive Approve, Reject, and View buttons. Click to act without leaving Slack.
• Agent error - Error message in a code block with warning indicator
• Agent online - Connection confirmation with check mark
• Budget threshold - Alerts at 80%, 90%, and 100% budget usage (deduped per threshold)
• Onboarding milestone - Celebrates an agent's first successful run

Interactive approvals

• Approve/reject buttons on every approval notification
• Clicking a button calls the Paperclip API and updates the Slack message inline
• Identifies which Slack user acted (logged as slack:{user_id})

Issue-thread confirmations

• Posts pending request_confirmation issue interactions to Slack with Accept/Reject buttons
• Clicking a button resolves the interaction in Paperclip and updates the Slack message inline
• Uses the approvals channel when configured, otherwise falls back to the default channel

HITL escalation

• Agents that get stuck can escalate to a dedicated Slack channel with full conversation context
• Rich Block Kit formatting with conversation history, agent reasoning, and confidence score
• "Use Suggested Reply" button when the agent has a best-guess response
• "Reply to Customer", "Override Agent", and "Dismiss" buttons
• Configurable timeout (default 15 min) with automatic default action (defer, close, retry)
• Customer messages queued during escalation and delivered with the human's response
• Exposes escalate_to_human tool for agents

Per-type channel routing

• Route approvals, errors, and pipeline events to separate Slack channels
• Falls back to the default channel when a per-type channel isn't configured
• Per-company overrides still take priority

Daily digest

• Scheduled job (9am daily) with real stats from the Paperclip API
• Tasks completed, tasks created, active agents, total cost, and top performer
• Cost data accumulated from cost_event.created events throughout the day

Phase 2: Multi-Agent Group Threads

• Multiple agents per thread - Spawn up to maxAgentsPerThread (default 5) agents in a single Slack thread via /clip acp spawn <agent> [display_name]
• @mention routing - @mention an agent name to direct your message to a specific agent; falls back to reply-to context, then most recently active
• Agent handoff - handoff_to_agent tool lets one agent request a handoff to another with Approve/Reject buttons in-thread
• Discussion loops - discuss_with_agent tool starts a back-and-forth conversation between two agents with configurable max turns
• Human checkpoints - Discussion pauses every 5 turns with Continue/Stop buttons so humans stay in the loop
• Stale detection - Discussions auto-pause after 5 minutes of inactivity
• Output sequencing - When multiple agents are active, outputs are queued and delivered in order with agent name labels
• Session registry - Tracks active/closed sessions per thread with native SDK sessions (preferred) and ACP fallback
• /clip acp status - Show all active agents in the current thread
• /clip acp close [name] - Close a specific agent or the most recently active one

Phase 3: Media-to-Task Pipeline

• Auto-detect media files - Audio (mp3, m4a, ogg, wav, webm, flac) and video (mp4, webm, quicktime) attachments in threads are automatically processed
• Whisper transcription - Audio files are sent to a whisper-transcriber agent for speech-to-text
• Brief Agent - Optional agent summarizes the transcription into an actionable brief
• Inline results - Transcription and brief run IDs posted back to the original thread
• process_media tool - Agents can programmatically trigger media processing with an optional briefAgentId
• Slack Events API - file_shared events trigger the pipeline automatically

Phase 4: Custom Workflow Commands

• !command syntax - Type !deploy staging or !triage bug-123 in any thread to trigger registered workflows
• Multi-step workflows - Each command runs a sequence of steps: invoke_agent, post_message, create_issue, wait_approval
• Argument interpolation - Use $1, $2, or $args in step templates to pass user arguments
• register_command tool - Agents or admins can register new commands at runtime
• Step-level approval gates - wait_approval steps pause execution with Approve/Reject buttons
• Progress indicators - Each step posts status to the thread; failures show error details
• /clip commands - List all registered custom commands with descriptions and usage

Phase 5: Proactive Agent Suggestions

• Event watches - register_watch tool sets up a trigger: when an event matching a pattern fires, an agent is invoked with a templated prompt
• Wildcard patterns - Match exact events (issue.created) or wildcards (agent.run.*)
• Prompt interpolation - Use ${event.payload.key} in watch prompts to inject event data
• Built-in sales templates - 5 pre-built watch templates: new-lead-follow-up, deal-stalled, high-value-issue, budget-warning, agent-error-diagnosis
• list_watch_templates tool - Browse available templates
• remove_watch tool - Remove watches by ID
• Scheduled check job - Watches are evaluated periodically against buffered events (last 100 per company)
• /clip watches - List all active watches with trigger counts

Slash commands

• /clip status - Show active agents and recent completions
• /clip agents - List all agents with status badges
• /clip issues [open|done] - List issues filtered by status
• /clip approve <id> - Approve a pending approval
• /clip acp spawn <agent> [display] - Add an agent to this thread
• /clip acp status - Show all agents in this thread
• /clip acp close [name] - Close a specific agent (or most recent)
• /clip commands - List registered custom commands
• /clip watches - List active event watches
• /clip help - Show this help message

Install

npm install paperclip-plugin-slack

Or register with your Paperclip instance directly:

curl -X POST http://127.0.0.1:3100/api/plugins/install \
  -H "Content-Type: application/json" \
  -d '{"packageName":"paperclip-plugin-slack"}'

[!NOTE] Company-scoped activation (#9557, first stable in v2026.720.0): the host now resolves plugin secret references under a company scope. This plugin is deliveries-only: it reads no configuration and resolves no secrets at startup, and builds its runtime from the host's company-scoped configuration delivery (onConfigChanged). On v2026.817.0+ it activates out of the box; on v2026.720.0 / 722.0 save the plugin configuration once through the settings panel after installing, to trigger the first delivery. The earlier temporary secret-ref kill switch (#5429) was removed upstream in #9557 — no host pinning is needed any more.

Troubleshooting: confirm your Paperclip host

If the plugin looks broken, first confirm which Paperclip host it's actually talking to. Run paperclipai plugin target (#8575) — it prints the resolved API URL plus the server's status, version, deploymentMode, and deploymentExposure before anything is installed. A server version older than this plugin expects is the most common cause of activation failures and secret-resolution errors (e.g. slackTokenRef not resolving) that look like plugin bugs but aren't. If the URL or version is wrong, retarget Paperclip — or update the server — before opening an issue.

Setup

1. Create a Slack app at https://api.slack.com/apps

2. Add the required bot scopes:

   • chat:write for posting notifications and command responses
   • commands for the /clip slash command
   • files:read if you want voice/file ingestion
   • app_mentions:read and the relevant message history scopes if you want Slack message events routed to agents

3. Choose one inbound mode:

   • Socket Mode: enable Socket Mode, create an app-level token with connections:write, and store that token as a Paperclip secret. Socket Mode is the easiest local setup because Slack sends events and interactive payloads over the WebSocket instead of requiring a public Request URL.
   • Webhook mode: keep Socket Mode disabled and configure the public Slack URLs below.

4. For webhook mode, configure these Slack app URLs:

   Slack setting	Request URL
   Event Subscriptions	<paperclip base URL>/api/plugins/paperclip-plugin-slack/webhooks/slack-events
   Slash Commands (/clip)	<paperclip base URL>/api/plugins/paperclip-plugin-slack/webhooks/slash-command
   Interactivity & Shortcuts	<paperclip base URL>/api/plugins/paperclip-plugin-slack/webhooks/slack-interactivity

5. Install the app to your workspace and copy the Bot OAuth Token

6. In Paperclip, create a company secret holding the Bot OAuth Token, by either:

   • UI: Open any agent's Configuration → Environment variables, enter a name (e.g. slack-bot-oauth-token) and the Bot OAuth Token as the value, then click Create / Seal. The secret is created at the company level (not bound to that agent — despite the agent-context UI) and the returned UUID can be used from any plugin in the company.
   • REST API: POST /api/companies/{companyId}/secrets with body {"name": "slack-bot-oauth-token", "value": "<your-bot-oauth-token>", "provider": "local_encrypted"}. The response contains the secret's UUID.

   Copy the resulting secret UUID — you'll paste it into slackTokenRef in the next step.

7. Install the plugin and configure the Bot token secret UUID in slackTokenRef, the app-level token secret UUID in slackAppTokenRef when using Socket Mode, the signing secret reference in slackSigningSecretRef, and your default channel ID. The host-delivered company owns all inbound commands and confirmation state. Leave slackAppTokenRef empty to keep webhook mode only.

Configuration

Agent tools

The plugin registers these tools that agents can call:

Migration

v2.0.1

The slackTokenRef field now declares format: "secret-ref", which is required for Paperclip to collect and resolve secret references at activation time. Previously, the field was a plain string with no format annotation, causing plugin activation to fail with Invalid secret reference.

If you installed v2.0.0: you must re-configure the plugin. Create a company secret holding the Slack Bot OAuth Token using one of the paths in the Setup section above (UI or REST API), then paste the resulting secret UUID into the slackTokenRef field in the plugin configuration. Raw token strings are no longer accepted in this field.

Development

npm install
npm run typecheck
npm test
npm run build

Tests cover notifications, approvals, escalation, session registry, media pipeline, custom commands, proactive suggestions, Block Kit formatting, Socket Mode, and slash commands.

For full local verification, run npm run verify. For the standalone diagnostic script only, set SLACK_APP_TOKEN and run npm run smoke:socket to verify that Slack returns a Socket Mode WebSocket URL. Installed plugin workers use slackAppTokenRef and paperclipApiKeyRef; they do not read host environment credentials or package .env files.

Contributing

Issues and PRs welcome at github.com/mvanhorn/paperclip-plugin-slack.

Auto-publishes to npm on push to main via OIDC trusted publishing.

Credits

@MatB57 - Escalation channel concept, "Chat OS" vision for turning chat plugins into bidirectional agent command centers, and the HITL suggested-reply flow.

License

MIT