fix(api): include content in octad GET responses

OctadResponse now returns title, body, metadata, and types from the
document and semantic modalities — previously only returned boolean
has_* flags. Also routes OctadInput.metadata into Document.metadata
during create/update so metadata survives roundtrip. This unblocks
downstream consumers (stapeln, hypatia) that need to read back stored
data. Fields use skip_serializing_if to keep responses clean when
modalities are unpopulated.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

Author: hyperpolymath

rust-core/verisim-api/src/lib.rs

@@ -374,11 +374,13 @@ pub struct TensorRequest {
     pub data: Vec<f64>,
 }
 
-/// Octad response
+/// Octad response — includes content from document and semantic modalities
+/// so consumers can read back what they stored (not just boolean flags).
 #[derive(Debug, Serialize, Deserialize)]
 pub struct OctadResponse {
     pub id: String,
     pub status: OctadStatusResponse,
+    // Modality presence flags
     pub has_graph: bool,
     pub has_vector: bool,
     pub has_tensor: bool,
@@ -388,6 +390,15 @@ pub struct OctadResponse {
     pub has_spatial: bool,
     pub version_count: u64,
     pub provenance_chain_length: u64,
+    // Content fields — returned when the modality is populated
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub title: Option<String>,
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub body: Option<String>,
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub metadata: Option<std::collections::HashMap<String, String>>,
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub types: Option<Vec<String>>,
 }
 
 /// Status response
@@ -400,6 +411,16 @@ pub struct OctadStatusResponse {
 
 impl From<&verisim_octad::Octad> for OctadResponse {
     fn from(h: &verisim_octad::Octad) -> Self {
+        let (title, body, metadata) = match &h.document {
+            Some(doc) => (
+                Some(doc.title.clone()),
+                if doc.body.is_empty() { None } else { Some(doc.body.clone()) },
+                if doc.metadata.is_empty() { None } else { Some(doc.metadata.clone()) },
+            ),
+            None => (None, None, None),
+        };
+        let types = h.semantic.as_ref().map(|s| s.types.clone());
+
         Self {
             id: h.id.to_string(),
             status: OctadStatusResponse {
@@ -416,6 +437,10 @@ impl From<&verisim_octad::Octad> for OctadResponse {
             has_spatial: h.spatial_data.is_some(),
             version_count: h.version_count,
             provenance_chain_length: h.provenance_chain_length,
+            title,
+            body,
+            metadata,
+            types,
         }
     }
 }

rust-core/verisim-octad/src/store.rs

@@ -430,11 +430,17 @@ where
         &self,
         id: &OctadId,
         input: &OctadDocumentInput,
+        extra_metadata: &HashMap<String, String>,
     ) -> Result<Document, OctadError> {
         let mut doc = Document::new(id.as_str(), &input.title, &input.body);
         for (key, value) in &input.fields {
             doc = doc.with_field(key, value);
         }
+        // Store OctadInput.metadata in Document.metadata so it roundtrips
+        // through GET responses.
+        for (key, value) in extra_metadata {
+            doc.metadata.insert(key.clone(), value.clone());
+        }
 
         self.document.index(&doc).await.map_err(|e| OctadError::ModalityError {
             modality: "document".to_string(),
@@ -804,7 +810,7 @@ where
 
         let mut document = None;
         if let Some(ref doc_input) = input.document {
-            match self.process_document(&id, doc_input).await {
+            match self.process_document(&id, doc_input, &input.metadata).await {
                 Ok(doc) => {
                     document = Some(doc);
                     modality_status.document = true;
@@ -1050,7 +1056,7 @@ where
 
         let mut document = None;
         if let Some(ref doc_input) = input.document {
-            match self.process_document(id, doc_input).await {
+            match self.process_document(id, doc_input, &input.metadata).await {
                 Ok(doc) => {
                     document = Some(doc);
                     modality_status.document = true;