Plugins

Micro-Seg is extensible through task plugins: WebAssembly components that run sandboxed, out-of-process in a dedicated plugin host. A misbehaving plugin cannot crash the app or read anything the host doesn’t hand it.

Plugins come in two kinds:

• Annotation tasks power the Interactive and Auto annotation flows (typically AI models)
• Extension tasks provide exports, analysis, summaries and tables, run from the Plugin Manager

Installing a plugin

Drop the plugin bundle into the user plugin directory:

• Windows: %APPDATA%/MicroSeg/data/plugins
• Linux: ~/.config/MicroSeg/data/plugins

A bundle is a directory tree of <plugin_id>/<version>/ containing plugin.json (the manifest), plugin.wasm, and optional assets. When the same plugin and version exists both built-in and user-installed, the user-installed copy wins.

Managing plugins

The Plugin Manager shows each task’s required context, permissions, capabilities and resource profile, and lets you enable or disable plugins individually. Disabled plugins are never executed.

Which plugin handles Interactive and Auto annotation is bound per project in <project_root>/.microseg/plugins.json, optionally pinned to a specific version.

Built-in plugins

Micro-Seg ships with:

• microseg.example.hrnetocr — interactive AI segmentation
• microseg.example.hrnetocr_automatic — automatic multi-seed segmentation
• microseg.example.extensions — example extension tasks

Developing plugins

Plugins are written in Rust against the plugin-tasks-sdk crate and compiled to a WASM component targeting the microseg:plugin/tasks@1.0.0 world.

A minimal plugin:

use plugin_tasks_sdk::prelude::*;

struct Plugin;

struct ExampleSession {
    seed_context: TaskSessionSeedContext,
}

impl SessionPlugin for Plugin {
    type Session = ExampleSession;

    fn open_session(
        task_id: String,
        seed_context: TaskSessionSeedContext,
    ) -> Result<Self::Session, TaskSessionError> {
        if task_id != "example.task" {
            return Err(error_invalid_request(format!(
                "unsupported task_id: {task_id}"
            )));
        }
        Ok(ExampleSession { seed_context })
    }
}

impl TaskSession for ExampleSession {
    fn run(&mut self) -> Result<TaskSessionResult, TaskSessionError> {
        let image_id = self.seed_context.require_active_image_id()?;
        let labels = read_label_schema()?;

        publish_progress(Some("Running example task"), Some(0.5))?;

        Ok(TaskSessionResult {
            summary: Some(format!("image={image_id}, labels={}", labels.labels.len())),
            artifacts: Vec::new(),
            tables: Vec::new(),
        })
    }
}

export_task_plugin!(Plugin);

Inside a session a plugin can query host state through typed require_ops (existing instances, label schema, occupancy, rasterization), submit incremental draft mutations with apply_ops, and publish progress, logs, summaries, tables and artifacts. The host commits or discards the session explicitly — only the committed batch is durable truth.

The full plugin contract, SDK and manifest templates are available on request — contact us.