@@ -63,6 +63,20 @@ const MOCK_BLOCKS = vi.hoisted(
         ],
         outputs: {},
       },
+      response: {
+        type: 'response',
+        category: 'blocks',
+        subBlocks: [
+          { id: 'dataMode', type: 'dropdown' },
+          {
+            id: 'data',
+            type: 'code',
+            language: 'json',
+            condition: { field: 'dataMode', value: 'json' },
+          },
+        ],
+        outputs: {},
+      },
       function: {
         type: 'function',
         category: 'blocks',
@@ -135,7 +149,74 @@ describe('collectUnquotedJsonStringReferences', () => {
       value: ['<start.order_id>'],
     })
     expect(findings[0]?.reason).toMatch(/^unquoted-json-string: /)
-    expect(findings[0]?.reason).toContain('"<start.order_id>"')
+  })
+
+  /**
+   * Quoting is only safe for text without a double quote, backslash, or control
+   * character, since the text is inserted raw; free text such as a model reply has
+   * to be built into JSON by a Function block instead.
+   */
+  it('advises quoting only for plain text and a Function block for free text', () => {
+    const [finding] = collectUnquotedJsonStringReferences(
+      graph({
+        start: START,
+        insert: insertRow('{"order_id": <start.order_id>}'),
+      })
+    )
+    expect(finding?.reason).toContain('"<start.order_id>"')
+    expect(finding?.reason).toMatch(
+      /double quote, backslash, line break, or other control character/
+    )
+    expect(finding?.reason).toMatch(/Function block/)
+    expect(finding?.reason).not.toMatch(/Quote each one/)
+  })
+
+  /**
+   * A field that is exactly one reference is the referenced value itself: the
+   * Response block returns text it cannot parse as-is and the API block sends a
+   * text body raw, while quoting it would turn JSON text into a JSON string.
+   */
+  it('accepts a field made only of string references, with no JSON around them', () => {
+    const findings = collectUnquotedJsonStringReferences(
+      graph({
+        writer: { type: 'agent', name: 'Writer' },
+        reply: {
+          type: 'response',
+          name: 'Reply',
+          subBlocks: { dataMode: { value: 'json' }, data: { value: '<writer.content>' } },
+        },
+        call: {
+          type: 'api',
+          name: 'Post',
+          subBlocks: { body: { value: '  <writer.content>\n' } },
+        },
+        signed: {
+          type: 'api',
+          name: 'Post Signed',
+          subBlocks: { body: { value: '<writer.content>\n\n<writer.content>' } },
+        },
+      })
+    )
+    expect(findings).toHaveLength(0)
+  })
+
+  it('still flags a string reference that sits inside JSON text around it', () => {
+    const findings = collectUnquotedJsonStringReferences(
+      graph({
+        writer: { type: 'agent', name: 'Writer' },
+        reply: {
+          type: 'response',
+          name: 'Reply',
+          subBlocks: { dataMode: { value: 'json' }, data: { value: '[<writer.content>]' } },
+        },
+        call: {
+          type: 'api',
+          name: 'Post',
+          subBlocks: { body: { value: '{"note": <writer.content>}' } },
+        },
+      })
+    )
+    expect(findings.map((finding) => finding.blockId)).toEqual(['reply', 'call'])
   })
 
   it('flags every unquoted string reference in the field once, including agent text', () => {
 
@@ -758,13 +758,26 @@ export function collectDanglingBlockOutputReferences(
  * `block.path` bodies of the reference tokens in JSON text that sit outside
  * every string literal, tokenized with the runtime's own reference scanner.
  * Tokens inside a literal, escaped quotes included, are already strings in the
- * parsed document.
+ * parsed document. A field made only of references has no JSON around them:
+ * the block receives the referenced text itself (Response returns text it
+ * cannot parse as-is, API sends it as a raw body), and quoting would only turn
+ * JSON text into a JSON string, so none of its tokens are reported.
  */
 function unquotedJsonReferenceTokens(json: string): string[] {
+  const tokens = findWorkflowReferenceTokens(json)
+  let outsideTokens = ''
+  let previousEnd = 0
+  for (const token of tokens) {
+    outsideTokens += json.slice(previousEnd, token.start)
+    previousEnd = token.end
+  }
+  outsideTokens += json.slice(previousEnd)
+  if (outsideTokens.trim() === '') return []
+
   const unquoted: string[] = []
   let cursor = 0
   let inString = false
-  for (const token of findWorkflowReferenceTokens(json)) {
+  for (const token of tokens) {
     for (; cursor < token.start; cursor++) {
       const char = json[cursor]
       if (inString && char === '\\') cursor++
@@ -784,7 +797,9 @@ function unquotedJsonReferenceTokens(json: string): string[] {
  * Outside Function code a reference is replaced by its raw text, so
  * `{"id": <start.order_id>}` becomes `{"id": ord-1}` and the block fails to
  * parse it at run time, while lint, deploy, and every earlier run of a draft
- * that never reached the block stay clean. Only references whose declared
+ * that never reached the block stay clean. No JSON-aware escaping exists
+ * outside Function code, so quoting is only safe for text that can never hold a
+ * quote, backslash, or control character. Only references whose declared
  * output type is `string` are reported: numbers, booleans, and objects already
  * resolve to JSON values, and an undeclared type cannot be judged here.
  */
@@ -835,7 +850,7 @@ export function collectUnquotedJsonStringReferences(
         field,
         value,
         kind: 'block-output',
-        reason: `unquoted-json-string: these references resolve to text, which is inserted without quotes, so the field is not valid JSON at run time unless the text is itself JSON. Quote each one, e.g. "${value[0]}".`,
+        reason: `unquoted-json-string: these references resolve to text, which is inserted raw, so the field is not valid JSON at run time unless the text is itself JSON. Quoting, e.g. "${value[0]}", works only for text that never contains a double quote, backslash, line break, or other control character, such as an id. For free text such as a model reply, build the JSON in a Function block, which reads references as values, and set this field to only that block's result reference.`,
       })
     }
   }