diff --git a/src/lib/__tests__/add-edge-modal.test.tsx b/src/lib/__tests__/add-edge-modal.test.tsx
index 53ac7e5..62f0db3 100644
--- a/src/lib/__tests__/add-edge-modal.test.tsx
+++ b/src/lib/__tests__/add-edge-modal.test.tsx
@@ -24,7 +24,7 @@ vi.mock("@/lib/mock-data", () => ({
 // ---------------------------------------------------------------------------
 let mockActiveModal: string | null = null
 let mockSourceRefId: string | null = null
-const mockClose = vi.fn()
+let mockClose = vi.fn()
 
 vi.mock("@/stores/modal-store", () => ({
   useModalStore: (sel: (s: Record<string, unknown>) => unknown) =>
@@ -74,6 +74,7 @@ function closeModal() {
 // ---------------------------------------------------------------------------
 describe("AddEdgeModal", () => {
   beforeEach(() => {
+    mockClose = vi.fn()
     vi.clearAllMocks()
     mockCreateEdge.mockResolvedValue({})
     closeModal()
diff --git a/src/lib/agent-api.ts b/src/lib/agent-api.ts
index df4e4be..fd4247a 100644
--- a/src/lib/agent-api.ts
+++ b/src/lib/agent-api.ts
@@ -41,108 +41,6 @@ async function buildSignedUrl(path: string): Promise<string> {
   return url.toString()
 }
 
-// Parse a single SSE line and return { event, data } or null
-function parseSseLine(line: string): { event: string; data: string } | null {
-  if (!line || line.startsWith(":")) return null
-  if (line.startsWith("data: ")) {
-    return { event: "message", data: line.slice(6) }
-  }
-  return null
-}
-
-// Process a stream of SSE data using ReadableStream
-async function processSSEStream(
-  reader: ReadableStreamDefaultReader<Uint8Array>,
-  opts: StreamAgentOpts,
-  retryFn: () => Promise<void>
-): Promise<void> {
-  const decoder = new TextDecoder()
-  let buffer = ""
-  let finalAnswer = ""
-  let citedRefIds: string[] = []
-  const activeToolCalls = new Map<string, ToolCallEvent>()
-
-  while (true) {
-    const { done, value } = await reader.read()
-    if (done) break
-
-    buffer += decoder.decode(value, { stream: true })
-    const lines = buffer.split("\n")
-    buffer = lines.pop() ?? ""
-
-    for (const line of lines) {
-      const parsed = parseSseLine(line.trim())
-      if (!parsed) continue
-
-      const raw = parsed.data
-      if (raw === "[DONE]") continue
-
-      try {
-        const chunk = JSON.parse(raw)
-
-        // AI SDK UI stream format
-        if (typeof chunk === "object" && chunk !== null) {
-          // Text delta
-          if (chunk.type === "text-delta" || chunk.type === "0") {
-            const delta = chunk.textDelta ?? chunk.value ?? ""
-            if (delta) {
-              finalAnswer += delta
-              opts.onChunk(delta)
-            }
-          }
-          // Tool call start
-          else if (chunk.type === "tool-call" || chunk.type === "9") {
-            const toolName = chunk.toolName ?? chunk.tool ?? ""
-            const toolCallId = chunk.toolCallId ?? chunk.id ?? String(Date.now())
-            const toolCall: ToolCallEvent = {
-              id: toolCallId,
-              tool: toolName,
-              params: chunk.args ?? chunk.params ?? {},
-              status: "in-flight",
-            }
-            activeToolCalls.set(toolCallId, toolCall)
-            opts.onToolCall({ ...toolCall })
-          }
-          // Tool result
-          else if (chunk.type === "tool-result" || chunk.type === "a") {
-            const toolCallId = chunk.toolCallId ?? chunk.id ?? ""
-            const existing = activeToolCalls.get(toolCallId)
-            if (existing) {
-              const resultCount =
-                chunk.result?.nodes?.length ?? chunk.result?.count ?? undefined
-              const updated: ToolCallEvent = {
-                ...existing,
-                status: "done",
-                resultCount,
-              }
-              activeToolCalls.set(toolCallId, updated)
-              opts.onToolCall({ ...updated })
-            }
-          }
-          // Done / finish
-          else if (chunk.type === "done" || chunk.type === "finish-message") {
-            if (chunk.answer) finalAnswer = chunk.answer
-            if (Array.isArray(chunk.cited_ref_ids)) citedRefIds = chunk.cited_ref_ids
-          }
-          // Error
-          else if (chunk.type === "error") {
-            opts.onError(new Error(chunk.error ?? "Agent error"))
-            return
-          }
-        }
-      } catch {
-        // Non-JSON lines are plain text deltas (some SSE formats)
-        if (raw && raw !== "[DONE]") {
-          finalAnswer += raw
-          opts.onChunk(raw)
-        }
-      }
-    }
-  }
-
-  opts.onDone({ answer: finalAnswer, cited_ref_ids: citedRefIds })
-}
-
 // Mock SSE stream for development
 async function mockStreamAgent(
   prompt: string,
@@ -213,7 +111,7 @@ export async function streamAgent(
 
     const headers: Record<string, string> = {
       "Content-Type": "application/json",
-      Accept: "text/event-stream",
+      Accept: "application/json",
     }
     if (l402) headers["Authorization"] = l402
 
@@ -224,7 +122,6 @@ export async function streamAgent(
         headers,
         body: JSON.stringify({
           prompt,
-          stream: true,
           sessionId: opts.sessionId,
         }),
         signal: opts.signal,
@@ -252,13 +149,18 @@ export async function streamAgent(
       return
     }
 
-    const reader = response.body?.getReader()
-    if (!reader) {
-      opts.onError(new Error("No response body"))
+    let data: { answer?: string; cited_ref_ids?: string[] }
+    try {
+      data = await response.json()
+    } catch {
+      opts.onError(new Error("Invalid JSON from agent"))
       return
     }
 
-    await processSSEStream(reader, opts, () => doRequest(true))
+    opts.onDone({
+      answer: data.answer ?? "",
+      cited_ref_ids: data.cited_ref_ids ?? [],
+    })
   }
 
   return doRequest()