Vellum has launched agent-to-agent communication inside Slack, enabling individual AI assistants to coordinate work with one another and with the people they represent. This approach differs from a single shared assistant that an entire team interacts with. On Vellum, each person operates their own assistant, which holds its own memory, context, and permissions. These separate assistants can now converse in a common Slack channel and move tasks forward between them.

The launch demonstration focused on planning a company offsite. Two assistants, one belonging to a team member named Marina and another to a colleague named Akash, took the task into a shared channel and collaborated on it. They divided responsibilities, negotiated candidate dates, and then one assistant reached out to the wider team for venue and dietary preferences before finalizing the arrangements. The sequence demonstrated assistants communicating with each other and with humans within the same thread, rather than a single system handling every request.

This capability is aimed at teams that already coordinate through Slack and want assistants that carry personal context into shared work. Since each assistant holds one person's history, preferences, and relationships, it can act as that person's representative when a plan requires input from several people. Permissions remain isolated by default, so one assistant accesses another's information only when necessary, and routine planning does not require anyone to restate context that an assistant already holds. Multi-step coordination, such as scheduling, collecting input, and confirming details, shifts from manual back-and-forth to assistants that manage the mechanics and present decisions to the people involved.

Vellum Labs, the company behind the assistant, has built its product around personal, on-device intelligence and aims to give people back the hours spent on daily logistics. Its assistant is positioned as software that runs on a user's own machine and acts on their behalf, drafting messages, managing calendars, and handling tasks while keeping data under the user's control. The Slack feature extends that personal-assistant model outward, connecting one user's assistant to others so a team of individually informed assistants can operate together. This marks a transition from a single-user helper to shared workflows, in which each participant maintains a distinct assistant rather than pooling everything into a single account.