diff --git a/crates/ethos-cli/src/cmd/rag.rs b/crates/ethos-cli/src/cmd/rag.rs
index 14c9435..147e2c3 100644
--- a/crates/ethos-cli/src/cmd/rag.rs
+++ b/crates/ethos-cli/src/cmd/rag.rs
@@ -16,6 +16,7 @@
 
 use std::collections::{BTreeMap, BTreeSet};
 
+use ethos_core::codes::WarningCode;
 use ethos_core::error::EthosError;
 use ethos_core::model::{Chunk, Document};
 
@@ -49,7 +50,11 @@ struct PageBounds {
 struct RagChunkRefs<'a> {
     page_bounds: BTreeMap<&'a str, PageBounds>,
     element_pages: BTreeMap<&'a str, &'a str>,
-    warning_codes: BTreeMap<&'a str, &'a str>,
+    element_span_refs: BTreeMap<&'a str, &'a [String]>,
+    element_warning_refs: BTreeMap<&'a str, &'a [String]>,
+    excluded_element_warnings: BTreeMap<&'a str, (&'a str, WarningCode)>,
+    excluded_span_warnings: BTreeMap<&'a str, (&'a str, WarningCode)>,
+    warning_codes: BTreeMap<&'a str, WarningCode>,
     schema_version: &'a str,
     document_fingerprint: &'a str,
     source_fingerprint: &'a str,
@@ -79,12 +84,50 @@ impl<'a> RagChunkRefs<'a> {
                 .iter()
                 .map(|element| (element.id.as_str(), element.page.as_str()))
                 .collect(),
+            element_span_refs: doc
+                .payload
+                .elements
+                .iter()
+                .map(|element| (element.id.as_str(), element.span_refs.as_slice()))
+                .collect(),
+            element_warning_refs: doc
+                .payload
+                .elements
+                .iter()
+                .map(|element| (element.id.as_str(), element.warning_refs.as_slice()))
+                .collect(),
+            excluded_element_warnings: doc
+                .payload
+                .security_warnings
+                .iter()
+                .chain(doc.payload.parser_warnings.iter())
+                .filter(|warning| excludes_from_default_chunks(warning.code))
+                .filter_map(|warning| {
+                    warning
+                        .element_ref
+                        .as_deref()
+                        .map(|element_ref| (element_ref, (warning.id.as_str(), warning.code)))
+                })
+                .collect(),
+            excluded_span_warnings: doc
+                .payload
+                .security_warnings
+                .iter()
+                .chain(doc.payload.parser_warnings.iter())
+                .filter(|warning| excludes_from_default_chunks(warning.code))
+                .filter_map(|warning| {
+                    warning
+                        .span_ref
+                        .as_deref()
+                        .map(|span_ref| (span_ref, (warning.id.as_str(), warning.code)))
+                })
+                .collect(),
             warning_codes: doc
                 .payload
                 .security_warnings
                 .iter()
                 .chain(doc.payload.parser_warnings.iter())
-                .map(|warning| (warning.id.as_str(), warning.code.as_str()))
+                .map(|warning| (warning.id.as_str(), warning.code))
                 .collect(),
             schema_version: doc.schema_version.as_str(),
             document_fingerprint: doc.fingerprint.as_str(),
@@ -94,6 +137,15 @@ impl<'a> RagChunkRefs<'a> {
     }
 }
 
+fn excludes_from_default_chunks(code: WarningCode) -> bool {
+    matches!(
+        code,
+        WarningCode::HiddenTextDetected
+            | WarningCode::OffPageTextDetected
+            | WarningCode::LowContrastTextDetected
+    )
+}
+
 fn validate_chunk_refs(chunk: &Chunk, refs: &RagChunkRefs<'_>) -> Result<(), Failure> {
     if chunk.element_refs.is_empty() {
         return Err(Failure::Usage(format!(
@@ -139,6 +191,7 @@ fn validate_chunk_refs(chunk: &Chunk, refs: &RagChunkRefs<'_>) -> Result<(), Fai
                 chunk.id, id, page
             )));
         }
+        validate_element_default_chunk_warnings(chunk, id, refs)?;
         backed_pages.insert(*page);
     }
     for (idx, bbox) in chunk.bboxes.iter().enumerate() {
@@ -178,11 +231,72 @@ fn validate_chunk_refs(chunk: &Chunk, refs: &RagChunkRefs<'_>) -> Result<(), Fai
         }
     }
     for id in &chunk.warning_refs {
-        if !refs.warning_codes.contains_key(id.as_str()) {
+        let Some(code) = refs.warning_codes.get(id.as_str()) else {
             return Err(Failure::Usage(format!(
                 "chunk {} references unknown warning_ref {}",
                 chunk.id, id
             )));
+        };
+        if excludes_from_default_chunks(*code) {
+            return Err(Failure::Usage(format!(
+                "chunk {} references default-excluded warning_ref {} ({})",
+                chunk.id,
+                id,
+                code.as_str()
+            )));
+        }
+    }
+    Ok(())
+}
+
+fn validate_element_default_chunk_warnings(
+    chunk: &Chunk,
+    element_ref: &str,
+    refs: &RagChunkRefs<'_>,
+) -> Result<(), Failure> {
+    for warning_ref in refs
+        .element_warning_refs
+        .get(element_ref)
+        .into_iter()
+        .flat_map(|warning_refs| warning_refs.iter())
+    {
+        let Some(code) = refs.warning_codes.get(warning_ref.as_str()) else {
+            continue;
+        };
+        if excludes_from_default_chunks(*code) {
+            return Err(Failure::Usage(format!(
+                "chunk {} element_ref {} carries default-excluded warning_ref {} ({})",
+                chunk.id,
+                element_ref,
+                warning_ref,
+                code.as_str()
+            )));
+        }
+    }
+    if let Some((warning_ref, code)) = refs.excluded_element_warnings.get(element_ref) {
+        return Err(Failure::Usage(format!(
+            "chunk {} element_ref {} carries default-excluded warning_ref {} ({})",
+            chunk.id,
+            element_ref,
+            warning_ref,
+            code.as_str()
+        )));
+    }
+    for span_ref in refs
+        .element_span_refs
+        .get(element_ref)
+        .into_iter()
+        .flat_map(|span_refs| span_refs.iter())
+    {
+        if let Some((warning_ref, code)) = refs.excluded_span_warnings.get(span_ref.as_str()) {
+            return Err(Failure::Usage(format!(
+                "chunk {} element_ref {} includes span_ref {} with default-excluded warning_ref {} ({})",
+                chunk.id,
+                element_ref,
+                span_ref,
+                warning_ref,
+                code.as_str()
+            )));
         }
     }
     Ok(())
@@ -245,7 +359,7 @@ fn rag_chunk_record(chunk: &Chunk, refs: &RagChunkRefs<'_>) -> Result<serde_json
             .warning_codes
             .get(id.as_str())
             .expect("chunk warning_refs validated before record serialization");
-        warnings.push(serde_json::Value::String(code.to_string()));
+        warnings.push(serde_json::Value::String(code.as_str().to_string()));
     }
     record.insert("warnings".into(), serde_json::Value::Array(warnings));
     Ok(serde_json::Value::Object(record))
diff --git a/crates/ethos-cli/tests/rag.rs b/crates/ethos-cli/tests/rag.rs
index 4ffd767..854e58c 100644
--- a/crates/ethos-cli/tests/rag.rs
+++ b/crates/ethos-cli/tests/rag.rs
@@ -318,3 +318,117 @@ fn rag_chunk_rejects_unknown_chunk_warning_ref() {
     assert!(String::from_utf8_lossy(&output.stderr)
         .contains("chunk c000001 references unknown warning_ref w999999"));
 }
+
+#[test]
+fn rag_chunk_rejects_default_excluded_chunk_warning_refs() {
+    for code in [
+        "hidden_text_detected",
+        "off_page_text_detected",
+        "low_contrast_text_detected",
+    ] {
+        let document = document_with_mutated_chunk(
+            &format!("default-excluded-{code}-chunk-document"),
+            |doc| {
+                doc["payload"]["security_warnings"][0]["code"] = serde_json::json!(code);
+                doc["payload"]["chunks"][0]["warning_refs"] = serde_json::json!(["w0001"]);
+            },
+        );
+        let output = run_ethos(&["rag", "chunk", document.to_str().unwrap()]);
+
+        assert_eq!(output.status.code(), Some(2));
+        assert_eq!(output.stdout, b"");
+        assert!(String::from_utf8_lossy(&output.stderr).contains(&format!(
+            "chunk c000001 references default-excluded warning_ref w0001 ({code})"
+        )));
+    }
+}
+
+#[test]
+fn rag_chunk_allows_non_exclusion_security_warning_ref() {
+    let document = document_with_mutated_chunk("non-exclusion-security-warning-document", |doc| {
+        doc["payload"]["security_warnings"][0]["code"] = serde_json::json!("annotations_present");
+        doc["payload"]["chunks"][0]["warning_refs"] = serde_json::json!(["w0001"]);
+    });
+    let output = run_ethos(&["rag", "chunk", document.to_str().unwrap()]);
+
+    assert!(
+        output.status.success(),
+        "ethos rag chunk failed\nstatus: {:?}\nstderr:\n{}",
+        output.status.code(),
+        String::from_utf8_lossy(&output.stderr)
+    );
+    assert_eq!(output.stderr, b"");
+    assert!(
+        String::from_utf8_lossy(&output.stdout).contains(r#""warnings":["annotations_present"]"#)
+    );
+}
+
+#[test]
+fn rag_chunk_rejects_default_excluded_element_warning_ref() {
+    let mut expected_element_id = String::new();
+    let document =
+        document_with_mutated_chunk("default-excluded-element-warning-document", |doc| {
+            expected_element_id = doc["payload"]["chunks"][0]["element_refs"][0]
+                .as_str()
+                .expect("fixture chunk element_ref is a string")
+                .to_string();
+            doc["payload"]["elements"][0]["warning_refs"] = serde_json::json!(["w0001"]);
+        });
+    let output = run_ethos(&["rag", "chunk", document.to_str().unwrap()]);
+
+    assert_eq!(output.status.code(), Some(2));
+    assert_eq!(output.stdout, b"");
+    assert!(String::from_utf8_lossy(&output.stderr).contains(&format!(
+        "chunk c000001 element_ref {expected_element_id} carries default-excluded warning_ref w0001 (hidden_text_detected)"
+    )));
+}
+
+#[test]
+fn rag_chunk_rejects_default_excluded_warning_attached_to_cited_element() {
+    let mut expected_element_id = String::new();
+    let document = document_with_mutated_chunk(
+        "default-excluded-attached-element-warning-document",
+        |doc| {
+            expected_element_id = doc["payload"]["chunks"][0]["element_refs"][0]
+                .as_str()
+                .expect("fixture chunk element_ref is a string")
+                .to_string();
+            doc["payload"]["security_warnings"][0]["element_ref"] =
+                serde_json::json!(expected_element_id.clone());
+        },
+    );
+    let output = run_ethos(&["rag", "chunk", document.to_str().unwrap()]);
+
+    assert_eq!(output.status.code(), Some(2));
+    assert_eq!(output.stdout, b"");
+    assert!(String::from_utf8_lossy(&output.stderr).contains(&format!(
+        "chunk c000001 element_ref {expected_element_id} carries default-excluded warning_ref w0001 (hidden_text_detected)"
+    )));
+}
+
+#[test]
+fn rag_chunk_rejects_default_excluded_span_warning_reached_by_cited_element() {
+    let mut expected_element_id = String::new();
+    let mut expected_span_id = String::new();
+    let document = document_with_mutated_chunk("default-excluded-span-warning-document", |doc| {
+        expected_element_id = doc["payload"]["chunks"][0]["element_refs"][0]
+            .as_str()
+            .expect("fixture chunk element_ref is a string")
+            .to_string();
+        expected_span_id = doc["payload"]["security_warnings"][0]["span_ref"]
+            .as_str()
+            .expect("fixture security warning span_ref is a string")
+            .to_string();
+        doc["payload"]["elements"][0]["span_refs"]
+            .as_array_mut()
+            .expect("fixture element span_refs are an array")
+            .push(serde_json::json!(expected_span_id.clone()));
+    });
+    let output = run_ethos(&["rag", "chunk", document.to_str().unwrap()]);
+
+    assert_eq!(output.status.code(), Some(2));
+    assert_eq!(output.stdout, b"");
+    assert!(String::from_utf8_lossy(&output.stderr).contains(&format!(
+        "chunk c000001 element_ref {expected_element_id} includes span_ref {expected_span_id} with default-excluded warning_ref w0001 (hidden_text_detected)"
+    )));
+}
diff --git a/schemas/ethos-chunks.schema.json b/schemas/ethos-chunks.schema.json
index fb65a83..6a66a3d 100644
--- a/schemas/ethos-chunks.schema.json
+++ b/schemas/ethos-chunks.schema.json
@@ -2,7 +2,7 @@
   "$schema": "https://json-schema.org/draft/2020-12/schema",
   "$id": "urn:ethos:schema:chunks:1",
   "title": "Ethos chunk record (one line of chunks.jsonl)",
-  "description": "Self-describing RAG chunk: each JSONL line carries provenance so a chunk can be cited and later verified without the full document at hand. Derived deterministically from the canonical document (ethos.json) — same document + same config => byte-identical chunks.jsonl. Warning codes are inlined (not refs) so RAG consumers need no join; hidden/off-page/low-contrast content is never present in default chunks.",
+  "description": "Self-describing default RAG chunk: each JSONL line carries provenance so a chunk can be cited and later verified without the full document at hand. Derived deterministically from the canonical document (ethos.json) — same document + same config => byte-identical chunks.jsonl. Warning codes are inlined (not refs) so RAG consumers need no join; hidden/off-page/low-contrast content is never present in default chunks.",
   "type": "object",
   "required": [
     "schema_version",
@@ -52,14 +52,11 @@
     },
     "warnings": {
       "type": "array",
-      "description": "Inherited warning codes from source regions (e.g. low_confidence_table_structure).",
+      "description": "Inherited warning codes from source regions that are still valid in default chunks. Text-exclusion security codes hidden_text_detected, off_page_text_detected, and low_contrast_text_detected are omitted from default chunks.",
       "items": {
         "enum": [
           "low_confidence_reading_order",
           "low_confidence_table_structure",
-          "hidden_text_detected",
-          "off_page_text_detected",
-          "low_contrast_text_detected",
           "annotations_present",
           "external_links_present",
           "image_only_page",
diff --git a/schemas/validate_examples.py b/schemas/validate_examples.py
index 44d9f9a..0c3d9d2 100644
--- a/schemas/validate_examples.py
+++ b/schemas/validate_examples.py
@@ -179,8 +179,20 @@ def c14n_line(v) -> str:
 
 
 wcodes = {w["id"]: w["code"] for w in p["security_warnings"] + p["parser_warnings"]}
+default_chunk_excluded_warning_codes = {
+    "hidden_text_detected",
+    "off_page_text_detected",
+    "low_contrast_text_detected",
+}
 expected_lines = []
 for ch in p["chunks"]:
+    for warning_ref in ch.get("warning_refs", []):
+        code = wcodes[warning_ref]
+        if code in default_chunk_excluded_warning_codes:
+            fail(
+                "document.example.json: "
+                f"chunk {ch['id']} references default-excluded warning_ref {warning_ref} ({code})"
+            )
     expected_lines.append(c14n_line({
         "schema_version": doc["schema_version"],
         "document_fingerprint": doc["fingerprint"],