Skills and Intents

At the heart of OVOS lies a powerful yet flexible intent handling system that enables voice-driven interaction. The system connects user utterances to developer-defined behavior through intents.

Key Concept

Skills register intent handlers. In practice, this means that:

  • A bus message representing a user intent is mapped to a specific piece of code—the intent handler—within a skill.
  • When the system detects that an utterance matches a registered intent, it emits the relevant bus message, and the corresponding handler is invoked.

How Intents Are Defined

Skill developers have two main ways to define intents:

1. Example Utterances

  • Developers write full example phrases that a user might say.
  • The engine learns patterns from these to match similar user utterances.
  • Example:
["what's the weather", "tell me the weather", "how's the forecast"]

2. Keyword Rules

  • Developers define combinations of required and optional keywords.
  • Rules are defined in a more structured way.
  • Example:
IntentBuilder("WeatherIntent")
.require("weather_keyword")
.optionally("location")

How OVOS Handles This

The OVOS Core is responsible for interpreting user utterances and deciding which (if any) intent they match. This is done by comparing the input against the limited training data (example phrases or keyword rules) provided by skill developers.

Modern Intent Pipelines

  • Historically:

    • Adapt was used for keyword-based matching.
    • Padatious was used for example-based matching.
    • These were inherited from Mycroft.

  • Now:

    • OVOS has evolved into a highly configurable intent pipeline framework.
    • Multiple intent engines can be used in parallel or sequence.

    • Skill developers and system integrators can choose or define:

      • Which engines to use
      • How to prioritize them
      • When to fall back or skip certain engines

Example Flow:

  1. User says: "What's the weather like tomorrow in Lisbon?"
  2. OVOS pipelines the utterance through configured engines.
  3. If an intent matches, a bus message like intent:WeatherIntent is emitted.
  4. The matching skill’s handler for WeatherIntent is called with the parsed data.

Summary

  • Intent = Message + Handler
  • Skills declare what they can handle; OVOS decides when to trigger them.
  • Intents are defined either via:
    • Full utterance examples
    • Structured keyword rules
  • Modern OVOS pipelines go beyond Padatious and Adapt, allowing advanced, modular configurations for intent parsing.