diff --git a/alembic/versions/033_add_thinking_text_to_messages.py b/alembic/versions/033_add_thinking_text_to_messages.py
new file mode 100644
index 00000000..4bfe991a
--- /dev/null
+++ b/alembic/versions/033_add_thinking_text_to_messages.py
@@ -0,0 +1,47 @@
+"""Add envelope-encrypted ``thinking_text`` column to messages.
+
+Captures the LLM's extended-thinking output (Anthropic ``thinking`` blocks)
+that ``MessageResponse`` returns alongside the final assistant text. Today
+the agent loop discards these blocks via ``get_response_text`` after the
+last LLM call lands; with this column populated, the assistant message row
+carries the reasoning that produced its ``body`` so admins can audit "why
+did the agent reply this way" without re-querying the LLM.
+
+Encrypted at rest under ``EncryptedString`` like ``body`` /
+``processed_context`` / ``tool_interactions_json``: the thinking stream
+quotes back user-supplied content (names, addresses, integration payloads)
+and would expose the same PII as the message body if left in plaintext.
+
+NOT NULL with a server default of empty string so existing rows
+backfill cleanly and raw-SQL inserts in older migration tests (which
+omit the column) keep working. Outbound messages persisted before this
+migration ran simply read back as empty thinking; inbound rows always
+have an empty value because the column is only written by the agent's
+outbound persistence path.
+
+Revision ID: 033
+Revises: 032
+Create Date: 2026-05-07
+"""
+
+from __future__ import annotations
+
+import sqlalchemy as sa
+
+from alembic import op
+
+revision: str = "033"
+down_revision: str = "032"
+branch_labels: tuple[str, ...] | None = None
+depends_on: tuple[str, ...] | None = None
+
+
+def upgrade() -> None:
+    op.add_column(
+        "messages",
+        sa.Column("thinking_text", sa.Text(), nullable=False, server_default=""),
+    )
+
+
+def downgrade() -> None:
+    op.drop_column("messages", "thinking_text")
diff --git a/backend/app/agent/core.py b/backend/app/agent/core.py
index 8973d87d..232b6c0f 100644
--- a/backend/app/agent/core.py
+++ b/backend/app/agent/core.py
@@ -35,7 +35,12 @@
     TurnEndEvent,
     TurnStartEvent,
 )
-from backend.app.agent.llm_parsing import ParsedToolCall, get_response_text, parse_tool_calls
+from backend.app.agent.llm_parsing import (
+    ParsedToolCall,
+    get_response_text,
+    get_response_thinking,
+    parse_tool_calls,
+)
 from backend.app.agent.messages import (
     AgentMessage,
     AssistantMessage,
@@ -181,6 +186,13 @@ class AgentResponse:
     # ``dispatch_reply_step`` so ``persist_outbound`` can store the user-facing
     # text instead of just ``reply_text`` (the LLM's prose, pre-receipts).
     dispatched_body: str = ""
+    # Concatenated extended-thinking text from the FINAL LLM response in the
+    # agent loop, captured from any ``ThinkingBlock`` content. Empty when the
+    # provider did not return thinking blocks (thinking disabled, or
+    # provider does not support extended thinking). ``persist_outbound``
+    # writes it onto the assistant message so admins can audit "why did
+    # the agent reply this way" without re-querying the LLM.
+    thinking_text: str = ""
 
 
 class ClawboltAgent:
@@ -1058,6 +1070,7 @@ async def process_message(
         memories_saved: list[dict[str, str]] = []
         tool_call_records: list[StoredToolInteraction] = []
         reply_text = ""
+        thinking_text = ""
         _total_input_tokens = 0
         _total_output_tokens = 0
         _total_cache_creation_tokens = 0
@@ -1141,12 +1154,26 @@ async def process_message(
                     total_cache_creation_input_tokens=_total_cache_creation_tokens,
                     total_cache_read_input_tokens=_total_cache_read_tokens,
                     system_prompt=system_prompt,
+                    # Surface any reasoning that preceded the error stop so
+                    # downstream observers (and a future persistence policy
+                    # that records error fallbacks) can see what the model
+                    # was working through before it bailed. Today
+                    # ``persist_outbound`` short-circuits on
+                    # ``is_error_fallback``, so this rides along the in-memory
+                    # response only.
+                    thinking_text=get_response_thinking(response),
                 )
 
             # Parse tool calls via shared parser
             parsed_raw = parse_tool_calls(response)
             if not parsed_raw:
                 reply_text = get_response_text(response)
+                # Capture thinking from the final response only. Earlier
+                # rounds produced tool calls and their thinking justifies
+                # a tool decision rather than the user-visible reply, so
+                # we keep the persisted record aligned with the message
+                # body the user actually saw.
+                thinking_text = get_response_thinking(response)
 
                 # Empty reply after tools is intentional silent action; do not re-prompt.
                 if not reply_text and actions_taken:
@@ -1239,6 +1266,7 @@ async def process_message(
         else:
             # Max rounds reached -- use last response content
             reply_text = get_response_text(response)
+            thinking_text = get_response_thinking(response)
             logger.debug("Max tool rounds (%d) reached, using last response", MAX_TOOL_ROUNDS)
 
         # Collect any messages dropped by reactive trimming (ContextLengthExceededError)
@@ -1290,6 +1318,7 @@ async def process_message(
             total_cache_creation_input_tokens=_total_cache_creation_tokens,
             total_cache_read_input_tokens=_total_cache_read_tokens,
             system_prompt=system_prompt,
+            thinking_text=thinking_text,
         )
 
     def _find_tool(self, name: str) -> Callable[..., Any] | None:
diff --git a/backend/app/agent/dto.py b/backend/app/agent/dto.py
index 010142c2..656e8b60 100644
--- a/backend/app/agent/dto.py
+++ b/backend/app/agent/dto.py
@@ -54,6 +54,7 @@ class StoredMessage(BaseModel):
     body: str = ""
     processed_context: str = ""
     tool_interactions_json: str = ""
+    thinking_text: str = ""
     external_message_id: str = ""
     media_urls_json: str = "[]"
     timestamp: str = Field(default_factory=lambda: datetime.datetime.now(datetime.UTC).isoformat())
diff --git a/backend/app/agent/heartbeat.py b/backend/app/agent/heartbeat.py
index 27b47f5e..d467292b 100644
--- a/backend/app/agent/heartbeat.py
+++ b/backend/app/agent/heartbeat.py
@@ -1043,6 +1043,7 @@ async def run_heartbeat_for_user(
             direction=MessageDirection.OUTBOUND,
             body=reply_text,
             tool_interactions_json=tool_interactions,
+            thinking_text=response.thinking_text if response else "",
         )
 
         # Record heartbeat log for persistent rate limiting
diff --git a/backend/app/agent/llm_parsing.py b/backend/app/agent/llm_parsing.py
index c61b21b0..2cb96f33 100644
--- a/backend/app/agent/llm_parsing.py
+++ b/backend/app/agent/llm_parsing.py
@@ -11,7 +11,7 @@
 from dataclasses import dataclass
 from typing import Any
 
-from any_llm.types.messages import MessageResponse, TextBlock, ToolUseBlock
+from any_llm.types.messages import MessageResponse, TextBlock, ThinkingBlock, ToolUseBlock
 
 logger = logging.getLogger(__name__)
 
@@ -76,3 +76,23 @@ def get_response_text(response: MessageResponse) -> str:
         if isinstance(block, TextBlock) and block.text:
             parts.append(block.text)
     return "".join(parts)
+
+
+def get_response_thinking(response: MessageResponse) -> str:
+    """Extract the extended-thinking text from a ``MessageResponse``.
+
+    Concatenates the ``thinking`` field across every ``ThinkingBlock``
+    in ``response.content``, separated by blank lines so multi-block
+    streams remain readable when rendered. Returns an empty string when
+    no thinking blocks are present (the model didn't think, or thinking
+    wasn't enabled in the request). Empty thinking blocks are skipped.
+
+    The cryptographic ``signature`` field on each block is not surfaced;
+    it is only meaningful for replaying the block back to Anthropic and
+    has no audit value to a human reader.
+    """
+    parts: list[str] = []
+    for block in response.content:
+        if isinstance(block, ThinkingBlock) and block.thinking:
+            parts.append(block.thinking)
+    return "\n\n".join(parts)
diff --git a/backend/app/agent/router.py b/backend/app/agent/router.py
index 4a6a855d..b0409cc6 100644
--- a/backend/app/agent/router.py
+++ b/backend/app/agent/router.py
@@ -447,6 +447,7 @@ async def persist_outbound(
         direction=MessageDirection.OUTBOUND,
         body=body,
         tool_interactions_json=tool_interactions,
+        thinking_text=response.thinking_text,
     )
 
 
diff --git a/backend/app/agent/session_db.py b/backend/app/agent/session_db.py
index 336dd326..578dac55 100644
--- a/backend/app/agent/session_db.py
+++ b/backend/app/agent/session_db.py
@@ -59,6 +59,7 @@ def _msg_to_stored(msg: Message) -> StoredMessage:
         body=msg.body,
         processed_context=msg.processed_context,
         tool_interactions_json=msg.tool_interactions_json,
+        thinking_text=msg.thinking_text,
         external_message_id=msg.external_message_id,
         media_urls_json=msg.media_urls_json,
         timestamp=ts,
@@ -205,6 +206,7 @@ def _delete_all_messages_for_session(cs_id: int) -> Delete[tuple[Message]]:
         "body",
         "processed_context",
         "tool_interactions_json",
+        "thinking_text",
         "external_message_id",
         "media_urls_json",
     }
@@ -361,6 +363,7 @@ async def add_message(
         media_urls_json: str = "[]",
         processed_context: str = "",
         tool_interactions_json: str = "",
+        thinking_text: str = "",
         channel: str = "",
     ) -> StoredMessage:
         """Deprecated alias of :meth:`add_message_async`."""
@@ -372,6 +375,7 @@ async def add_message(
             media_urls_json=media_urls_json,
             processed_context=processed_context,
             tool_interactions_json=tool_interactions_json,
+            thinking_text=thinking_text,
             channel=channel,
         )
 
@@ -384,6 +388,7 @@ async def add_message_async(
         media_urls_json: str = "[]",
         processed_context: str = "",
         tool_interactions_json: str = "",
+        thinking_text: str = "",
         channel: str = "",
     ) -> StoredMessage:
         """Insert a message into the database and update the in-memory session."""
@@ -415,6 +420,7 @@ async def add_message_async(
                 body=body,
                 processed_context=processed_context,
                 tool_interactions_json=tool_interactions_json,
+                thinking_text=thinking_text,
                 external_message_id=external_message_id,
                 media_urls_json=media_urls_json,
                 timestamp=now,
@@ -432,6 +438,7 @@ async def add_message_async(
                 body=body,
                 processed_context=processed_context,
                 tool_interactions_json=tool_interactions_json,
+                thinking_text=thinking_text,
                 external_message_id=external_message_id,
                 media_urls_json=media_urls_json,
                 timestamp=now.isoformat(),
@@ -457,6 +464,7 @@ async def add_message_by_session_id(
         media_urls_json: str = "[]",
         processed_context: str = "",
         tool_interactions_json: str = "",
+        thinking_text: str = "",
         channel: str = "",
     ) -> StoredMessage:
         """Deprecated alias of :meth:`add_message_by_session_id_async`."""
@@ -468,6 +476,7 @@ async def add_message_by_session_id(
             media_urls_json=media_urls_json,
             processed_context=processed_context,
             tool_interactions_json=tool_interactions_json,
+            thinking_text=thinking_text,
             channel=channel,
         )
 
@@ -480,6 +489,7 @@ async def add_message_by_session_id_async(
         media_urls_json: str = "[]",
         processed_context: str = "",
         tool_interactions_json: str = "",
+        thinking_text: str = "",
         channel: str = "",
     ) -> StoredMessage:
         """Insert a message using only the session_id (no SessionState needed).
@@ -506,6 +516,7 @@ async def add_message_by_session_id_async(
                 body=body,
                 processed_context=processed_context,
                 tool_interactions_json=tool_interactions_json,
+                thinking_text=thinking_text,
                 external_message_id=external_message_id,
                 media_urls_json=media_urls_json,
                 timestamp=now,
@@ -521,6 +532,7 @@ async def add_message_by_session_id_async(
                 body=body,
                 processed_context=processed_context,
                 tool_interactions_json=tool_interactions_json,
+                thinking_text=thinking_text,
                 external_message_id=external_message_id,
                 media_urls_json=media_urls_json,
                 timestamp=now.isoformat(),
diff --git a/backend/app/models.py b/backend/app/models.py
index ba871ad8..77b0137e 100644
--- a/backend/app/models.py
+++ b/backend/app/models.py
@@ -282,14 +282,17 @@ class Message(Base):
     """A single message in a conversation, inbound or outbound.
 
     User-authored content (``body``, ``processed_context``,
-    ``tool_interactions_json``) is envelope-encrypted at rest via
-    ``EncryptedString``. ``body`` is the raw text the user / channel
-    sent; ``processed_context`` is the same content after media
+    ``tool_interactions_json``, ``thinking_text``) is envelope-encrypted
+    at rest via ``EncryptedString``. ``body`` is the raw text the user /
+    channel sent; ``processed_context`` is the same content after media
     transcription / OCR / preprocessing; ``tool_interactions_json``
     holds tool call args / results that frequently embed customer
     names, phone numbers, and addresses passed to QuickBooks /
-    CompanyCam / calendar tools. The decrypt path runs transparently
-    on every ORM read, so application code keeps reading
+    CompanyCam / calendar tools. ``thinking_text`` holds the LLM's
+    extended-thinking blocks for outbound messages (empty for inbound),
+    which can quote user content back at length and so receives the
+    same encryption treatment. The decrypt path runs transparently on
+    every ORM read, so application code keeps reading
     ``msg.tool_interactions_json`` and gets plaintext JSON.
 
     Other text columns intentionally left plaintext:
@@ -316,6 +319,11 @@ class Message(Base):
     tool_interactions_json: Mapped[str] = mapped_column(
         EncryptedString(table="messages", column="tool_interactions_json"), default=""
     )
+    thinking_text: Mapped[str] = mapped_column(
+        EncryptedString(table="messages", column="thinking_text"),
+        default="",
+        server_default="",
+    )
     external_message_id: Mapped[str] = mapped_column(String, default="")
     media_urls_json: Mapped[str] = mapped_column(Text, default="")
     timestamp: Mapped[datetime] = mapped_column(
diff --git a/tests/test_llm_parsing.py b/tests/test_llm_parsing.py
index bed3c314..e3304039 100644
--- a/tests/test_llm_parsing.py
+++ b/tests/test_llm_parsing.py
@@ -1,14 +1,26 @@
 """Tests for shared LLM response parsing utilities."""
 
 import json
-
-from any_llm.types.messages import MessageResponse, MessageUsage, TextBlock, ToolUseBlock
-
-from backend.app.agent.llm_parsing import ParsedToolCall, get_response_text, parse_tool_calls
+from typing import Any
+
+from any_llm.types.messages import (
+    MessageResponse,
+    MessageUsage,
+    TextBlock,
+    ThinkingBlock,
+    ToolUseBlock,
+)
+
+from backend.app.agent.llm_parsing import (
+    ParsedToolCall,
+    get_response_text,
+    get_response_thinking,
+    parse_tool_calls,
+)
 from tests.mocks.llm import make_text_response, make_tool_call_response
 
 
-def _make_response(blocks: list[TextBlock | ToolUseBlock]) -> MessageResponse:
+def _make_response(blocks: list[Any]) -> MessageResponse:
     """Helper to build a MessageResponse from content blocks.
 
     Uses ``model_construct`` to bypass pydantic validation so tests can
@@ -117,3 +129,51 @@ def test_returns_empty_for_empty_content(self) -> None:
         """Should return empty string when content list is empty."""
         resp = _make_response([])
         assert get_response_text(resp) == ""
+
+
+class TestGetResponseThinking:
+    def test_returns_thinking_block_text(self) -> None:
+        """A single thinking block should be returned verbatim."""
+        resp = _make_response(
+            [
+                ThinkingBlock(
+                    type="thinking",
+                    thinking="The user wants to know about X. I should look up Y.",
+                    signature="sig",
+                ),
+                TextBlock(type="text", text="Here is what I found."),
+            ]
+        )
+        assert get_response_thinking(resp) == "The user wants to know about X. I should look up Y."
+
+    def test_concatenates_multiple_thinking_blocks_with_blank_line(self) -> None:
+        """Multiple thinking blocks join with a blank line for readability."""
+        resp = _make_response(
+            [
+                ThinkingBlock(type="thinking", thinking="First thought.", signature=""),
+                TextBlock(type="text", text="reply"),
+                ThinkingBlock(type="thinking", thinking="Second thought.", signature=""),
+            ]
+        )
+        assert get_response_thinking(resp) == "First thought.\n\nSecond thought."
+
+    def test_returns_empty_when_no_thinking_blocks(self) -> None:
+        """A response with text and tool blocks but no thinking returns empty."""
+        resp = make_text_response("plain reply")
+        assert get_response_thinking(resp) == ""
+
+    def test_skips_empty_thinking_blocks(self) -> None:
+        """An empty thinking string should not produce a stray separator."""
+        resp = _make_response(
+            [
+                ThinkingBlock(type="thinking", thinking="", signature=""),
+                ThinkingBlock(type="thinking", thinking="real thought", signature=""),
+                ThinkingBlock(type="thinking", thinking="", signature=""),
+            ]
+        )
+        assert get_response_thinking(resp) == "real thought"
+
+    def test_returns_empty_for_empty_content(self) -> None:
+        """Empty content list returns empty thinking."""
+        resp = _make_response([])
+        assert get_response_thinking(resp) == ""
diff --git a/tests/test_session_db_async.py b/tests/test_session_db_async.py
index 5dbd17e0..7a5acef1 100644
--- a/tests/test_session_db_async.py
+++ b/tests/test_session_db_async.py
@@ -161,6 +161,38 @@ async def test_add_message_async_inserts_and_assigns_seq(
     assert session.messages[-1].body == "hello"
 
 
+async def test_add_message_async_round_trips_thinking_text(
+    async_db: async_sessionmaker,
+) -> None:
+    """Outbound messages persist and re-read the LLM's extended-thinking text.
+
+    Guards three things at once: the new ``thinking_text`` column is
+    written by ``add_message_async``, the ``EncryptedString`` decorator
+    round-trips the value (a non-envelope value would raise on read), and
+    the in-memory ``StoredMessage`` carries the same field so callers do
+    not have to re-fetch.
+    """
+    user_id = await _create_user(async_db)
+    store = SessionStore(user_id)
+    session, _ = await store.get_or_create_session_async()
+
+    saved = await store.add_message_async(
+        session,
+        direction="outbound",
+        body="here is the answer",
+        thinking_text="step 1: parse the ask\nstep 2: pick the tool\nstep 3: phrase the reply",
+    )
+    assert saved.thinking_text == (
+        "step 1: parse the ask\nstep 2: pick the tool\nstep 3: phrase the reply"
+    )
+
+    reloaded = await store.load_session_async(session.session_id)
+    assert reloaded is not None
+    assert reloaded.messages[-1].thinking_text == (
+        "step 1: parse the ask\nstep 2: pick the tool\nstep 3: phrase the reply"
+    )
+
+
 async def test_add_message_by_session_id_async_assigns_seq_independently(
     async_db: async_sessionmaker,
 ) -> None: