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Agent

.md

Agent frames, prompt drafts, agent settings and permissions.

An agent frame is one coding-agent session running on the host’s machine. Everyone on the board reads the same thread.

Pick an agent

A new agent frame asks which agent runs it. The list is what the host has installed:

  • Claude Code, through its ACP adapter.
  • opencode, as opencode acp.

The choice is made once per frame, and the frame is renamed after it: agent-1 becomes claude-1.

A new agent frame: choose an agent

Prompt drafts

The composer at the bottom is a shared prompt draft: everyone with edit access types into it at once and sees each other’s carets. Send (⌘/Ctrl-Enter) sends the draft as one prompt, signed with the sender’s name.

Two people writing one prompt draft

Who can send:

  • the host, and trusted guests, directly;
  • guests with edit access, after the host approves (Guests).

Stop ends the agent’s turn.

Thread

The thread shows each prompt with its author, the agent’s replies, and its tool calls, which expand. The status in the header is idle, running, or waiting (for a permission). Board tool calls show as canvas · open_frame and the like.

A thread: the prompt, the agent’s tool calls, and its reply

Agent settings

The chip in the composer (for example Haiku 4.5) opens the agent’s settings: model, reasoning effort, mode, whatever the agent offers for the session. They can change between prompts. The agent decides which settings exist, and they can depend on the model.

Settings are kept with the session and applied again when the agent restarts.

Agent settings for Claude Code: model and mode

Permissions

Agents ask before some tool calls: Claude Code in its Manual mode, opencode before every shell command. The request appears in the thread, under the tool call it gates. Only the host can answer it, whatever the guest access; guests see that it waits for the host.

Host Guest
A permission request, with the host’s answers The same request for a guest: waiting for the host

Sessions

  • A session’s agent process starts when it is needed and stops after 15 minutes unused. The next prompt resumes the same conversation.
  • Threads are saved by canvas serve and survive restarts.
  • Removing an agent frame removes it from the board; the session’s log stays in .canvas/.

Configuration

Environment variable Default Effect
CANVAS_OPENCODE_MODEL opencode-go/big-pickle opencode’s model for new sessions

opencode runs with bash: "ask", so every shell command asks the host.