Document utterance embedding handoff

schemas/README.md

@@ -20,7 +20,7 @@ steer the machine, describe its authority here.
   for projecting interlingua through agent state into flavored English.
 - [english-pronunciation-plan.md](./english-pronunciation-plan.md): plan for
   stringing flavored English into IPA/phoneme sequences before downstream speech.
-- [line-expression-vector.md](./line-expression-vector.md): learned vector
+- [utterance-embedding-handoff.md](./utterance-embedding-handoff.md): learned utterance embedding handoff
   contract for handing prosody, emphasis, and character pressure to downstream
   synth control.
 

schemas/line-expression-vector.md

@@ -1,32 +0,0 @@
-# Line Expression Vector Contract
-
-This is the human-facing schema receipt for Weksa line-expression vectors.
-
-The vector sits after flavored-English lowering and before AquaSynth synth
-control. It is the learned representation of a character's line: meaning,
-emphasis, prosody, and delivery pressure in one compact artifact.
-
-## Required Fields
-
-- `schema_version`: currently `weksa.line_expression_vector.v0`.
-- `source_output_ref`: lowered English output reference.
-- `speaker_agent_id`: speaker identity.
-- `encoder`: model ID and version metadata.
-- `text`: spoken and normalized text.
-- `vector`: dimensionality and either inline values or `values_ref`.
-- `audit_projection`: human-readable probe of what the vector is intended to
-  preserve.
-- `trace`: notes and uncertainties.
-
-## Boundary
-
-The vector is not canonical character state. It is a derived runtime/training
-artifact.
-
-The audit projection is not the true latent space. It is a review surface for
-humans, tests, and training data.
-
-## Downstream
-
-AquaSynth may consume the vector through its own decoder. Weksa does not define
-the synth-control schema here.

schemas/utterance-embedding-handoff.md

@@ -0,0 +1,37 @@
+# Utterance Embedding Handoff Contract
+
+This is the human-facing schema receipt for Weksa-to-AquaSynth utterance
+embedding handoff packets.
+
+The packet sits after flavored-English lowering and before AquaSynth speech
+control. It carries the inspected inputs for a learned utterance embedding:
+speech text embedding, prosody/emphasis hints, and a projected character-state
+vector from the speaker's Ghostlight/Epiphany-shaped profile.
+
+## Required Fields
+
+- `schema_version`: currently `weksa.utterance_embedding_handoff.v0`.
+- `source_output_ref`: lowered English output reference.
+- `speaker_agent_id`: speaker identity.
+- `text`: spoken and normalized text.
+- `inputs.speech_text_embedding`: model metadata, dimensionality, and values or
+  `values_ref`.
+- `inputs.prosody_emphasis_hints`: compact deterministic hints for emphasis,
+  contour, pace, intensity, and pause pressure.
+- `inputs.character_state_vector`: projected speaker-state vector and source.
+- `utterance_embedding`: AquaSynth-owned model metadata and produced vector
+  reference when available.
+- `audit_projection`: human-readable probe of what the embedding should
+  preserve.
+- `trace`: notes and uncertainties.
+
+## Boundary
+
+Weksa owns the packet ingredients and audit surface. AquaSynth owns the learned
+encoder, gradient descent, synth-driver model, and audio evaluation.
+
+The utterance embedding is not canonical character state. It is a derived
+runtime/training artifact.
+
+The audit projection is not the true latent space. It is a review surface for
+humans, tests, and training data.