Plugins & Skills (Extensibility)

Purpose

Extend the agent without touching core code: install plugins from marketplaces, add custom slash commands, custom tools, hooks, and drop markdown skills the agent can load on demand.

How it works

• src/extensibility/ is the umbrella:
  • plugins/ - plugin lifecycle: manager.ts, loader.ts, installer.ts, parser.ts, git-url.ts, doctor.ts, marketplace/ (sources + marketplace-auto-update), and legacy pi compat.
  • custom-commands/, custom-tools/, extensions/, hooks/ - user additions registered with the session.
  • skills.ts - loads markdown skills from configured directories; skills live under ~/.omp/agent/ (user) and .omp/ (project) trees and are scanned with scanSkillsFromDir.
  • slash-commands.ts, tool-proxy.ts - wiring for the above into the registry and tool loop.
• /plugins [list|enable|disable] manages installed plugins; /marketplace manages marketplace sources and installs.

Configuration

skills:
  enabled: true                # master toggle (schema default: true)
  enableSkillCommands: ...     # allow `/skill:<name>` invocation
  enableAgentsUser: true       # read .agents user-level skills
  enableAgentsProject: true    # read .agents project-level skills
  enablePiUser: true           # read .pi user-level skills
  enablePiProject: true        # read .pi project-level skills
marketplace:
  autoUpdate: ...              # plugin marketplace auto-update

Skill discovery mirrors the capability system used by MCP and agents: scanSkillsFromDir + compareSkillOrder in src/discovery/helpers.ts.

Real example

> /plugins list
> /marketplace search <term>
> load coding skill           # agent loads a skill by name on demand

Failure behavior

• A broken plugin package surfaces errors from doctor.ts/loader.ts instead of corrupting the session.
• Marketplace auto-update failures leave the currently installed version in place.

Limitations

• Plugin/skill ecosystem is opinionated about directory layout; skills in the wrong tree simply aren’t discovered.
• Marketplace features are implemented but have no committed test.