An AI Agent for Slack and ClickUp, Plus an MCP Server and API
Postellite works as an AI agent for Slack and ClickUp, so your team can hand over marketing work where it already talks. Developers can reach the same agents through an MCP server and a REST API.
Mention the agent in Slack and watch it work
Install the Postellite app, then mention or message it in your channels like any teammate.
Install the App
Add the Postellite app to your Slack workspace.
Mention or Message It
Ask for a report, an article or a refresh in a channel or a direct message.
Follow Live Progress
The agent shows its progress in Slack while it works.
Approve or Cancel
Before it acts, the agent asks with Approve and Cancel buttons.
Verified Result
After acting, it checks its own work before reporting back.
Choose how much the Slack agent does without asking
Assign marketing tasks to Postellite in ClickUp
Postellite gets its own ClickUp account, so it takes work the same way the rest of your team does. ClickUp is available on the Agency plan.
Its Own Account
Postellite joins ClickUp as a member with its own account.
Mention or Assign
Mention it on a task, or assign it a task directly.
Replies in Comments
The agent reports progress and results in the task comments.
Approve by Reply
Reply approve or cancel in the comments to decide on a change.
Closes Only When Verified
The task is closed only after the work has been checked.
Shared workspace memory
Slack, ClickUp and web chat share one memory
The agents in Slack and ClickUp reach the same business memory as the web chat. Your documents, policies and connected accounts come along, so nobody has to re-explain the client.
Use Postellite from Claude Code, Claude Desktop or Cursor
The Postellite MCP server comes with copy-paste setup and exposes every agent tool for the workspace.
Claude Code
Call Postellite's workspace tools from your terminal sessions.
Claude Desktop
Ask for research, content and publishing work from a desktop chat.
Cursor
Reach your marketing workspace from inside the editor.
Any MCP Client
Includes list_workspaces, switch_workspace, list_agents and get_agent to move between clients and agents.
Your tools, Postellite's workspace
Ask the agent and schedule posts from your own code
A small REST API covers the most common jobs. Authenticate with an API key.
Ask the Agent
POST /api/v1/agent sends a request to the agent, with threads for follow-ups.
Schedule, List and Cancel Posts
/api/v1/posts manages scheduled posts from your own systems.
Account Info
The /api/v1/me endpoint is part of the same REST API v1.
Personal & Workspace Keys
Personal keys work across all your workspaces. Workspace keys stay in one. Revoke either at any time.
Hand Marketing Work to Postellite Where Your Team Already Works
Mention the agent in Slack, assign it in ClickUp, or call it from Claude Code, Cursor and your own code. Approvals and verification come with it.
Slack is available from the Growth plan. ClickUp is available on the Agency plan.