Encoder Coverage Map

Encoder	Intended Scenario	What It Encodes	Primary Output	Cited Example/Test
`HGraphEncoder`	General state encoding with optional goals/actions/history	Objects, facts, optional goal/action/history structures	`BatchEncoding` (hetero)	`examples/encoders/hetero_encoder_example.py`, `tests/encoding/test_batch_encoding.py`
`FlatRelationEncoder`	Compact packed state/goal/action/history encoding	Packed relation tensors plus target-entity metadata	`BatchEncoding` (flat-on-homo carrier)	`examples/encoders/flat_relation_encoder_example.py`, `tests/encoding/test_flat_relation_encoder.py`
`HorizonEncoder`	Root + lookahead candidate reasoning	Root state with `TransitionDAG` target/candidate relations	`BatchEncoding` (hetero)	`examples/encoders/horizon_hetero_encoder_example.py`, `tests/encoding/test_horizon_encoder.py`
`FlatHorizonEncoder`	Compact root + lookahead candidate reasoning	Packed flat relations with state-target carrier rows from `TransitionDAG`	`BatchEncoding` (flat-on-homo carrier)	`tests/encoding/test_flat_horizon_encoder.py`
`TransitionHGraphEncoder`	Full transition modeling	Source + successor structures in one transition graph	`BatchEncoding` (hetero)	`examples/encoders/transition_hetero_encoder_example.py`, `tests/encoding/test_transition_hetero_encoder.py`
`TransitionEffectsHGraphEncoder`	Effect/delta transition learning	Transition-focused deltas/effects representation	`BatchEncoding` (hetero)	`examples/encoders/transition_change_hetero_encoder_example.py`, `tests/encoding/test_transition_change_encoder.py`
`FlatTransitionEncoder`	Compact full transition modeling	One-step successor encoding over the flat state-target substrate	`BatchEncoding` (flat-on-homo carrier)	`examples/encoders/flat_transition_encoder_example.py`, `tests/encoding/test_flat_transition_encoder.py`
`FlatTransitionEffectsEncoder`	Compact effect/delta transition learning	One-step delta/effects encoding over the flat state-target substrate	`BatchEncoding` (flat-on-homo carrier)	`examples/encoders/flat_transition_encoder_example.py`, `tests/encoding/test_flat_transition_encoder.py`
`ColorEncoder`	Compact homogeneous baselines	Integer-style color/object/predicate/action features	`BatchEncoding` (homo)	`examples/encoders/color_encoder_example.py`, `tests/encoding/test_color_encoder.py`
`ILGEncoder`	Python ILG feature construction	ILG atom/object/action topology and statuses	`BatchEncoding` (hetero)	`examples/encoders/ilg_hetero_encoder_example.py`, `tests/encoding/test_custom_python_encoder_example.py`

Backend Support

All encoders in the table accept Pymimir and PyTyr inputs through a per-instance runtime. Either planner can be installed independently, or both can coexist in one process. Compatible outputs from different backends share semantic schema fingerprints and can be passed together to mifrost.batch_encodings.

Capability	Pymimir	PyTyr
Single and batch encoding	Yes	Yes
Stream encoding	Yes	Yes
HGraph relation-schema replacement	Yes	Yes
Explicit or inferred selection	Yes	Yes
Independent wheel/install	Yes	Yes
Same-process coexistence	Yes	Yes
Mixed compatible `BatchEncoding` / PyG / serialization	Yes	Yes

transition_dag_from_rustworkx(...) remains a Pymimir-returning standalone helper for backward compatibility. For either backend, passing the raw rustworkx.PyDiGraph directly to the selected HorizonEncoder or FlatHorizonEncoder uses that runtime's native conversion path.

Streams and Dynamic Fields Coverage

Stream semantics/parity: tests/encoding/test_stream_encoder.py
Flat stream semantics/parity: tests/encoding/test_flat_stream_encoder.py
Dynamic graph fields/collation: tests/encoding/test_dynamic_graph_fields.py

LGAN Surface

HGraphEncoder and FlatRelationEncoder share the same main-lane LGAN API: include_lgan_edges, lgan_*_edge_pos, and lgan_anchor_sources.
HorizonEncoder and FlatHorizonEncoder use candidate state rows as LGAN anchors and do not expose lgan_anchor_sources.
Transition encoders on both lanes follow the horizon rule.