arcana-core 0.2.0

The OS that gives your agents a soul — core library

arcana-core

The Python library at the heart of Arcana OS. Assign a tarot card to an agent: get a soul.

pip install arcana-core
# or inside the monorepo:
uv sync --all-packages --all-extras

---

Quick start

Agents run through a ModelGateway. The gateway owns connections, routing, retries, and cost metering; the agent just names the model it wants.

from arcana import Agent, Card
from arcana.models import ConnectionStore, ModelGateway

async with ModelGateway(ConnectionStore()) as gw:
    agent = Agent(
        name="researcher",
        card=Card.HERMIT,
        gateway=gw,
        model="ollama/hermes-3",
    )

    result = await agent.run("Summarise recent advances in RAG.")
    print(result)

    # Streaming
    async for chunk in agent.stream("What is a vector index?"):
        print(chunk, end="", flush=True)

---

How it works

Every agent is configured by a tarot card. The card encodes an archetype: personality and default temperature. The CardEngine blends one primary card with optional modifier cards into an AgentConfig, which the Agent wires together with the gateway.

Card enum
  → CardRegistry.get()   → TarotCard  (archetype, traits, prompt ingredients)
  → CardEngine.resolve() → AgentConfig (system_prompt, temperature)
  → Agent.__init__()      ← wires gateway + model + AgentConfig together
  → Agent.run() / Agent.stream()

Blending: primary card = 70%, modifier cards = 30% split equally. Temperature is linearly blended. CardEngine.check_compatibility() reports how well a primary and its modifiers fit together.

agent = Agent(
    name="creative-researcher",
    card=Card.HERMIT,            # 70 % — deep, methodical
    modifier_cards=[Card.FOOL],  # 30 % — curious, action-first
    gateway=gw,
    model="ollama/hermes-3",
)

Each run records a Session (messages + token totals). Sessions are stateless in this release — multi-turn continuity within a session is supported; cross-session memory is not yet wired (see the roadmap).

---

The 22 Major Arcana

#	Card	Archetype	Default temp
0	The Fool	Explorer / Autonomous Agent	0.95
I	The Magician	Executor / Tool Master	0.50
II	The High Priestess	Archivist / Pattern Reader	0.40
III	The Empress	Creator / Generative Agent	0.85
IV	The Emperor	Orchestrator / System Agent	0.30
V	The Hierophant	Advisor / Domain Expert	0.30
VI	The Lovers	Collaborator / Communication	0.70
VII	The Chariot	Driver / Goal Agent	0.40
VIII	Strength	Coach / Long-Game Agent	0.60
IX	The Hermit	Researcher / Deep Analyst	0.35
X	Wheel of Fortune	Scheduler / Probabilistic	0.65
XI	Justice	Auditor / Evaluation Agent	0.20
XII	The Hanged Man	Reframer / Perspective	0.80
XIII	Death	Transformer / Refactor Agent	0.40
XIV	Temperance	Integrator / Synthesis	0.55
XV	The Devil	Shadow / Constraint Breaker	0.75
XVI	The Tower	Disruptor / Breakthrough	0.85
XVII	The Star	Companion / Wellbeing Agent	0.70
XVIII	The Moon	Interpreter / Ambiguity	0.80
XIX	The Sun	Amplifier / Output Agent	0.75
XX	Judgement	Reviewer / Reflection	0.45
XXI	The World	Meta-Agent (reserved)	0.50

The World (XXI) is defined but reserved — it cannot be assigned to an agent yet.

---

Module map

Module	What's implemented
arcana/types/	All Pydantic models — always import from arcana.types. Covers cards, agents, sessions, and models.
arcana/cards/definitions/	One file per card, each exporting a TarotCard instance (all 22 present).
arcana/cards/registry.py	CardRegistry — get(Card), all().
arcana/cards/engine.py	CardEngine — blending, resolve() → AgentConfig, check_compatibility().
arcana/agents/agent.py	Agent — run() / stream(), session recording.
arcana/agents/registry.py	AgentRegistry — CRUD for agent records persisted to ~/.arcana/agents/{id}/agent.json; build_runtime().
arcana/agents/session_manager.py	SessionManager — session lifecycle, persisted to disk.
arcana/models/	ModelGateway (routing, adapter pooling, retry/backoff, error normalization, cost metering), adapters for Ollama / Anthropic / OpenAI-compatible, ConnectionStore (keyring-backed secrets), pricing, and a normalized ModelError hierarchy.

Types convention

All Pydantic models are re-exported from arcana.types. Always import from there:

from arcana.types import Card, AgentConfig  # correct
from arcana.types.card import Card           # avoid

---

Adding a new card

1. Create arcana/cards/definitions/<name>.py following fool.py — export a single TarotCard instance.
2. Import it in arcana/cards/definitions/__init__.py and add it to all_cards() in canonical order.
3. Add the Card enum value to arcana/types/card.py if not already present.

---

Development

# Lint
uv run ruff check .

# Type check
uv run pyright packages/arcana-core/arcana

# Tests (no LLM calls)
uv run pytest packages/arcana-core/tests/ -v -m "not llm_eval"

---

Roadmap

This release ships the Phase 1a MVP: card-configured, stateless agents on the model gateway. The memory type system (MemoryEntry, MemoryProfile, MemoryWeights) is already modelled and the Agent has memory slots ready — federated memory backends, a tool/MCP gateway, and The World meta-agent land in Phase 1b as additive wiring, not a rewrite.