diff --git a/ui-opentui/src/test/tools.test.tsx b/ui-opentui/src/test/tools.test.tsx
index d41e6f7dc2..55ab3e89b1 100644
--- a/ui-opentui/src/test/tools.test.tsx
+++ b/ui-opentui/src/test/tools.test.tsx
@@ -14,7 +14,7 @@ import { describe, expect, test } from 'vitest'
 import { createSessionStore, type ToolPartState } from '../logic/store.ts'
 import { App } from '../view/App.tsx'
 import { ThemeProvider } from '../view/theme.tsx'
-import { BashToolBody } from '../view/tools/bashTool.tsx'
+import { BashToolBody, commandOf } from '../view/tools/bashTool.tsx'
 import { renderProbe, type RenderProbe } from './lib/render.ts'
 
 type Store = ReturnType<typeof createSessionStore>
@@ -234,3 +234,91 @@ describe('bash tool renderer — command + full output (Epic 2.4)', () => {
     }
   })
 })
+
+describe('redaction precedence — gateway args_text wins over raw args (security)', () => {
+  // The gateway redacts verbose `args_text` (server.py _tool_args_text) but
+  // sends the raw `args` dict on tool.complete UNREDACTED. structuredArgs must
+  // parse argsText first so masked secrets never render unmasked.
+
+  test('labeled fields render the redacted args_text value, never the raw args secret', async () => {
+    const store = createSessionStore()
+    seedTool(
+      store,
+      // verbose session: tool.start carries the gateway-redacted args_text
+      {
+        tool_id: 's1',
+        name: 'mcp_call',
+        args_text: JSON.stringify({ api_key: 'sk-****', endpoint: 'v1/users' }, null, 2)
+      },
+      // tool.complete carries the raw, UNREDACTED args dict
+      {
+        tool_id: 's1',
+        name: 'mcp_call',
+        args: { api_key: 'sk-secret123', endpoint: 'v1/users' },
+        result_text: 'done'
+      }
+    )
+
+    const probe = await mountApp(store)
+    try {
+      await clickHeader(probe, 'mcp_call')
+      const expanded = await probe.waitForFrame(f => f.includes('api_key'))
+      expect(expanded).toContain('sk-****') // the gateway's redaction survives
+      expect(expanded).not.toContain('sk-secret123') // the raw secret never renders
+      expect(expanded).toContain('endpoint') // non-secret fields still labeled
+      expect(expanded).toContain('v1/users')
+    } finally {
+      probe.destroy()
+    }
+  })
+
+  test('commandOf prefers the redacted args_text parse over the raw args command', () => {
+    const store = createSessionStore()
+    seedTool(
+      store,
+      {
+        tool_id: 's2',
+        name: 'terminal',
+        args_text: JSON.stringify({ command: 'curl -H "Authorization: sk-****" api.test' })
+      },
+      {
+        tool_id: 's2',
+        name: 'terminal',
+        args: { command: 'curl -H "Authorization: sk-secret123" api.test' },
+        result_text: 'ok'
+      }
+    )
+    // Going through the real store also pins the invariant this fix relies on:
+    // tool.complete back-fills argsText only when ABSENT — the redacted
+    // tool.start args_text is never overwritten.
+    const last = store.state.messages[store.state.messages.length - 1]
+    const part = last?.parts?.find((p): p is ToolPartState => p.type === 'tool' && p.id === 's2')
+    expect(part).toBeDefined()
+    expect(part?.argsText).toContain('sk-****')
+    const cmd = commandOf(part as ToolPartState)
+    expect(cmd).toContain('sk-****') // a masked command IS the correct display
+    expect(cmd).not.toContain('sk-secret123')
+  })
+
+  test('absent or unparseable argsText falls back to raw args (non-verbose parity)', () => {
+    // no argsText at all → raw args, same as the previous behavior
+    const bare: ToolPartState = {
+      type: 'tool',
+      id: 's3',
+      name: 'terminal',
+      state: 'complete',
+      args: { command: 'ls -la' }
+    }
+    expect(commandOf(bare)).toBe('ls -la')
+    // argsText capped mid-JSON (unparseable) → raw args still render
+    const capped: ToolPartState = {
+      type: 'tool',
+      id: 's4',
+      name: 'terminal',
+      state: 'complete',
+      args: { command: 'echo hi' },
+      argsText: '{"command": "echo h'
+    }
+    expect(commandOf(capped)).toBe('echo hi')
+  })
+})
diff --git a/ui-opentui/src/view/tools/bashTool.tsx b/ui-opentui/src/view/tools/bashTool.tsx
index 48f2c61046..a24d21ece9 100644
--- a/ui-opentui/src/view/tools/bashTool.tsx
+++ b/ui-opentui/src/view/tools/bashTool.tsx
@@ -21,7 +21,9 @@ import { defaultSubtitle, resultLines, structuredArgs, ToolOutputBlock } from '.
 import type { ToolBodyProps, ToolRenderer } from './registry.tsx'
 
 /** The verbatim invocation: terminal `command` / execute_code `code` /
- *  process `action [session_id]`; else the gateway's argsPreview. */
+ *  process `action [session_id]`; else the gateway's argsPreview. Via
+ *  structuredArgs this prefers the gateway-redacted args_text parse — a
+ *  masked command string is the CORRECT display when the gateway redacted it. */
 export function commandOf(part: ToolPartState): string {
   const args = structuredArgs(part)
   if (args) {
diff --git a/ui-opentui/src/view/tools/defaultTool.tsx b/ui-opentui/src/view/tools/defaultTool.tsx
index baba81bbdb..8ea163ad9b 100644
--- a/ui-opentui/src/view/tools/defaultTool.tsx
+++ b/ui-opentui/src/view/tools/defaultTool.tsx
@@ -24,16 +24,26 @@ export const EXPANDED_MAX = 200
 /** Max labeled arg fields shown when expanded. */
 const FIELDS_MAX = 16
 
-/** The tool's structured args: `part.args` (tool.complete) or parsed argsText. */
+/**
+ * The tool's structured args. SECURITY: parse `part.argsText` FIRST — when it
+ * came from the gateway's verbose `args_text` (tool.start) it is REDACTED
+ * (server.py `_tool_args_text` masks secrets), while the raw `args` dict on
+ * `tool.complete` is sent unredacted. The store never overwrites a tool.start
+ * argsText — `tool.complete` only back-fills it by stringifying raw `args`
+ * when absent (store.ts) — so this precedence yields redacted values whenever
+ * the gateway sent them, and the same raw args as before otherwise. Raw
+ * `part.args` is the fallback when argsText is absent or unparseable.
+ */
 export function structuredArgs(part: ToolPartState): Record<string, unknown> | undefined {
-  if (part.args) return part.args
-  if (!part.argsText) return undefined
-  try {
-    const o: unknown = JSON.parse(part.argsText)
-    return o && typeof o === 'object' && !Array.isArray(o) ? (o as Record<string, unknown>) : undefined
-  } catch {
-    return undefined
+  if (part.argsText) {
+    try {
+      const o: unknown = JSON.parse(part.argsText)
+      if (o && typeof o === 'object' && !Array.isArray(o)) return o as Record<string, unknown>
+    } catch {
+      /* unparseable argsText (e.g. capped mid-JSON) — fall back to raw args */
+    }
   }
+  return part.args
 }
 
 function isPrimitive(v: unknown): v is string | number | boolean {