Slack opens shared coding channels to custom AI agents with a new API

Custom coding agents can now open a shared Slack workspace for a task, rather than keep their work inside a conversation with one person. Slack released its Code API on October 28, making the developer interface generally available on all plans so teams can follow, redirect and review agent work together.

From a mention to a task workspace

The unit of work is a code channel: a dedicated space an agent creates for a particular task. It brings together the people, files, context and plan needed for the job. Teammates can watch progress, supply missing information and approve changes without leaving Slack.

Developers add the API to an agent’s manifest—its configuration—and set channel properties such as its name, commands and views. A teammate can then mention the agent in a channel or direct message. When the request needs more than a quick answer, the agent can create a separate code channel and add bookmarks and work outputs for others to follow.

The interface supports code diffs, which show proposed changes, alongside HTML previews and the agent’s thinking steps. Slack supplies those display tools so developers do not have to build separate screens for that work. The agent can post status updates as it proceeds and archive the channel when the task is finished.

Shared steering, existing permissions

A task does not have to stay with the person who started it. Slack says a coworker can enter a code channel, see the execution history and steer the agent. Its example is an on-call engineer spotting that an agent is investigating the wrong service, then redirecting it while another teammate adds context. That is an illustrative workflow, not a reported customer result.

According to Slack, agents inherit the permissions and administrator controls of the channel where they work. Message compliance uses existing workspace controls and data boundaries, rather than a separate access model developers must create. People can approve high-stakes changes, and the record remains searchable after the channel is archived.

More than 150Customers and partners requesting access

Slack says more than 150 customers and partners asked to build code-channel experiences for their own agents.

30%GitHub Copilot agent sessions opening code channels

Slack reports this usage figure for GitHub Copilot; it is not a measure across all agents.

The API is live; review upgrades come later

Slack Code launched in August with partners including Anthropic, Cognition, GitHub and Vercel. Until this release, only a handful of partners could build these channel experiences. General availability opens the same underlying tools to developers building internal enterprise agents or agents intended for the Slack Marketplace.

The accompanying Pull Request improvements are still described as available soon. A pull request is a proposed code change submitted for review. Slack plans to let users request GitHub reviews from Slack, sync comments in both directions and receive a prompt to merge from the code channel once approval and tests are complete.

Slack offers three starting routes:

• Build an agent using the API documentation and add the API to its manifest.
• Submit a customer-facing agent to the Slack Marketplace for teams to find and install.
• Try an existing Slack Code agent, including Claude, Devin, GitHub Copilot or Vercel, before building.