fix(opencode-plugin): per-session workflow toggle with agent filter and TUI sidebar sync

.opencode/commands/workflow.md

@@ -9,10 +9,14 @@ Toggle workflows for the current session:
 - `/wf on` - Enable workflows (shorthand)
 - `/wf off` - Disable workflows (shorthand)
 
-When workflows are disabled, the plugin will not inject development instructions or enforce file edit restrictions.
+The override is per-session only and resets when the session ends.
 
-You can also set the initial state via environment variable:
+---
+
+You can also restrict which agents have workflows active by default via `WORKFLOW_ACTIVE_AGENTS`:
 
 ```bash
-WORKFLOW=off opencode
+WORKFLOW_ACTIVE_AGENTS=agent1,agent2,agentN opencode
 ```
+
+When not set, workflows are active for all agents. `/workflow on` overrides this for the current session.

packages/opencode-plugin/README.md

@@ -79,6 +79,30 @@ Or for local development:
 
 Integrated with `@codemcp/workflows-core` for real state management and phase-based file restrictions.
 
+## Configuration
+
+### Agent filtering
+
+By default the plugin is active for all agents. Set `WORKFLOW_ACTIVE_AGENTS` to a comma-separated list of agent names to restrict it to specific agents only:
+
+```bash
+# Only activate for the "coder" and "architect" agents
+WORKFLOW_ACTIVE_AGENTS=coder,architect
+```
+
+When the env var is set, workflow hooks and edit restrictions are skipped for any agent not in the list. Workflow tools are still registered, and calling them from an inactive agent will result in an error. This prevents subagents (Tasks) from being interrupted by workflow instructions when they are not expected to follow the workflow.
+
+### Session override
+
+Use the `/workflow` command to toggle the plugin on or off for the current session, regardless of the agent filter:
+
+```
+/workflow off   # disable for this session
+/workflow on    # enable for this session (overrides WORKFLOW_ACTIVE_AGENTS filter)
+```
+
+`/workflow on` acts as a full escape hatch — it forces workflows active even if the current agent is not listed in `WORKFLOW_ACTIVE_AGENTS`.
+
 ## Related
 
 - [`@codemcp/workflows-core`](../core) — The workflow engine (shared with MCP server)