fix(memory): standardize tool parameter names (#9552)

fix(memory): standardize tool parameter names

    Use old_string/new_string across memory edit tools, docs, tests, and starter kits to avoid mismatched parameter names.

    👾 Generated with [Letta Code](https://letta.com)

    Co-Authored-By: Letta <noreply@letta.com>
    EOF
    )

fern/pages/agents/base_tools.mdx

@@ -0,0 +1,150 @@
+---
+title: Base Tools
+subtitle: Built-in tools for memory management and user communication
+slug: guides/agents/base-tools
+---
+
+Base tools are built-in tools that enable memory management, user communication, and access to conversation history and archival storage.
+
+## Available Base Tools
+
+| Tool | Purpose |
+|------|---------|
+| `memory_insert` | Insert text into a memory block |
+| `memory_replace` | Replace specific text in a memory block |
+| `memory_rethink` | Completely rewrite a memory block |
+| `memory_finish_edits` | Signal completion of memory editing |
+| `conversation_search` | Search prior conversation history |
+| `archival_memory_insert` | Add content to archival memory |
+| `archival_memory_search` | Search archival memory |
+| `send_message` | Send a message to the user (legacy architectures only) |
+
+## Memory Block Editing
+
+Memory blocks are editable sections in the agent's context window. These tools let agents update their own memory.
+
+See the [Memory Blocks guide](/guides/agents/memory-blocks) for more about how memory blocks work.
+
+### memory_insert
+
+Insert text at a specific line in a memory block.
+
+**Parameters:**
+- `label`: Which memory block to edit
+- `new_string`: Text to insert
+- `insert_line`: Line number (0 for beginning, -1 for end)
+
+**Common uses:**
+- Add new information to the end of a block
+- Insert context at the beginning
+- Add items to a list
+
+### memory_replace
+
+Replace specific text in a memory block.
+
+**Parameters:**
+- `label`: Which memory block to edit
+- `old_string`: Exact text to find and replace
+- `new_string`: Replacement text
+
+**Common uses:**
+- Update outdated information
+- Fix typos or errors
+- Delete text (by replacing with empty string)
+
+**Important:** The `old_string` must match exactly, including whitespace. If it appears multiple times, the tool will error.
+
+### memory_rethink
+
+Completely rewrite a memory block's contents.
+
+**Parameters:**
+- `label`: Which memory block to rewrite
+- `new_memory`: Complete new contents
+
+**When to use:**
+- Condensing cluttered information
+- Major reorganization
+- Combining multiple pieces of information
+
+**When not to use:**
+- Adding one line (use `memory_insert`)
+- Changing specific text (use `memory_replace`)
+
+### memory_finish_edits
+
+Signals that memory editing is complete.
+
+**Parameters:** None
+
+Some agent architectures use this to mark the end of a memory update cycle.
+
+## Recall Memory
+
+### conversation_search
+
+Search prior conversation history using both text matching and semantic similarity.
+
+**Parameters:**
+- `query`: What to search for
+- `roles`: Optional filter by message role (user, assistant, tool)
+- `limit`: Maximum number of results
+- `start_date`, `end_date`: ISO 8601 date/datetime filters (inclusive)
+
+**Returns:**
+Matching messages with role and content, ordered by relevance.
+
+**Example queries:**
+- "What did the user say about deployment?"
+- "Find previous responses about error handling"
+- "Search tool outputs from last week"
+
+## Archival Memory
+
+Archival memory stores information long-term outside the context window. See the [Archival Memory documentation](/guides/agents/archival-memory) for details.
+
+### archival_memory_insert
+
+Add content to archival memory for long-term storage.
+
+**Parameters:**
+- `content`: Text to store
+- `tags`: Optional tags for organization
+
+**Common uses:**
+- Storing reference information for later
+- Saving important context that doesn't fit in memory blocks
+- Building a knowledge base over time
+
+### archival_memory_search
+
+Search archival memory using semantic (embedding-based) search.
+
+**Parameters:**
+- `query`: What to search for semantically
+- `tags`: Optional tag filters
+- `tag_match_mode`: "any" or "all" for tag matching
+- `top_k`: Maximum results
+- `start_datetime`, `end_datetime`: ISO 8601 filters (inclusive)
+
+**Returns:**
+Matching passages with timestamps and content, ordered by semantic similarity.
+
+## Deprecated Tools
+
+These tools are still available but deprecated:
+
+| Tool | Use Instead |
+|------|-------------|
+| `send_message` | Agent responses (no tool needed). See [legacy architectures](/guides/legacy/memgpt_agents_legacy) |
+| `core_memory_append` | `memory_insert` with `insert_line=-1` |
+| `core_memory_replace` | `memory_replace` |
+
+## Related Documentation
+
+- [Memory Blocks](/guides/agents/memory-blocks)
+- [Archival Memory](/guides/agents/archival-memory)
+- [Utilities](/guides/agents/prebuilt-tools)
+- [Multi-Agent Tools](/guides/agents/multi-agent)
+- [Custom Tools](/guides/agents/custom-tools)

letta/functions/function_sets/base.py

@@ -308,116 +308,118 @@ SNIPPET_LINES: int = 4
 
 
 # Based off of: https://github.com/anthropics/anthropic-quickstarts/blob/main/computer-use-demo/computer_use_demo/tools/edit.py?ref=musings.yasyf.com#L154
-def memory_replace(agent_state: "AgentState", label: str, old_str: str, new_str: str) -> str:  # type: ignore
+def memory_replace(agent_state: "AgentState", label: str, old_string: str, new_string: str) -> str:  # type: ignore
     """
     The memory_replace command allows you to replace a specific string in a memory block with a new string. This is used for making precise edits.
     Do NOT attempt to replace long strings, e.g. do not attempt to replace the entire contents of a memory block with a new string.
 
     Args:
         label (str): Section of the memory to be edited, identified by its label.
-        old_str (str): The text to replace (must match exactly, including whitespace and indentation).
-        new_str (str): The new text to insert in place of the old text. Do not include line number prefixes.
+        old_string (str): The text to replace (must match exactly, including whitespace and indentation).
+        new_string (str): The new text to insert in place of the old text. Do not include line number prefixes.
 
     Examples:
         # Update a block containing information about the user
-        memory_replace(label="human", old_str="Their name is Alice", new_str="Their name is Bob")
+        memory_replace(label="human", old_string="Their name is Alice", new_string="Their name is Bob")
 
         # Update a block containing a todo list
-        memory_replace(label="todos", old_str="- [ ] Step 5: Search the web", new_str="- [x] Step 5: Search the web")
+        memory_replace(label="todos", old_string="- [ ] Step 5: Search the web", new_string="- [x] Step 5: Search the web")
 
         # Pass an empty string to
-        memory_replace(label="human", old_str="Their name is Alice", new_str="")
+        memory_replace(label="human", old_string="Their name is Alice", new_string="")
 
         # Bad example - do NOT add (view-only) line numbers to the args
-        memory_replace(label="human", old_str="1: Their name is Alice", new_str="1: Their name is Bob")
+        memory_replace(label="human", old_string="1: Their name is Alice", new_string="1: Their name is Bob")
 
         # Bad example - do NOT include the line number warning either
-        memory_replace(label="human", old_str="# NOTE: Line numbers shown below (with arrows like '1→') are to help during editing. Do NOT include line number prefixes in your memory edit tool calls.\\n1→ Their name is Alice", new_str="1→ Their name is Bob")
+        memory_replace(label="human", old_string="# NOTE: Line numbers shown below (with arrows like '1→') are to help during editing. Do NOT include line number prefixes in your memory edit tool calls.\\n1→ Their name is Alice", new_string="1→ Their name is Bob")
 
         # Good example - no line numbers or line number warning (they are view-only), just the text
-        memory_replace(label="human", old_str="Their name is Alice", new_str="Their name is Bob")
+        memory_replace(label="human", old_string="Their name is Alice", new_string="Their name is Bob")
 
     Returns:
         str: The updated value of the memory block.
     """
     import re
 
-    if bool(re.search(r"\nLine \d+: ", old_str)):
+    if bool(re.search(r"\nLine \d+: ", old_string)):
         raise ValueError(
-            "old_str contains a line number prefix, which is not allowed. Do not include line numbers when calling memory tools (line numbers are for display purposes only)."
+            "old_string contains a line number prefix, which is not allowed. Do not include line numbers when calling memory tools (line numbers are for display purposes only)."
         )
-    if CORE_MEMORY_LINE_NUMBER_WARNING in old_str:
+    if CORE_MEMORY_LINE_NUMBER_WARNING in old_string:
         raise ValueError(
-            "old_str contains a line number warning, which is not allowed. Do not include line number information when calling memory tools (line numbers are for display purposes only)."
+            "old_string contains a line number warning, which is not allowed. Do not include line number information when calling memory tools (line numbers are for display purposes only)."
         )
-    if bool(re.search(r"\nLine \d+: ", new_str)):
+    if bool(re.search(r"\nLine \d+: ", new_string)):
         raise ValueError(
-            "new_str contains a line number prefix, which is not allowed. Do not include line numbers when calling memory tools (line numbers are for display purposes only)."
+            "new_string contains a line number prefix, which is not allowed. Do not include line numbers when calling memory tools (line numbers are for display purposes only)."
         )
 
-    old_str = str(old_str).expandtabs()
-    new_str = str(new_str).expandtabs()
+    old_string = str(old_string).expandtabs()
+    new_string = str(new_string).expandtabs()
     current_value = str(agent_state.memory.get_block(label).value).expandtabs()
 
-    # Check if old_str is unique in the block
-    occurences = current_value.count(old_str)
+    # Check if old_string is unique in the block
+    occurences = current_value.count(old_string)
     if occurences == 0:
-        raise ValueError(f"No replacement was performed, old_str `{old_str}` did not appear verbatim in memory block with label `{label}`.")
+        raise ValueError(
+            f"No replacement was performed, old_string `{old_string}` did not appear verbatim in memory block with label `{label}`."
+        )
     elif occurences > 1:
         content_value_lines = current_value.split("\n")
-        lines = [idx + 1 for idx, line in enumerate(content_value_lines) if old_str in line]
+        lines = [idx + 1 for idx, line in enumerate(content_value_lines) if old_string in line]
         raise ValueError(
-            f"No replacement was performed. Multiple occurrences of old_str `{old_str}` in lines {lines}. Please ensure it is unique."
+            f"No replacement was performed. Multiple occurrences of old_string `{old_string}` in lines {lines}. Please ensure it is unique."
         )
 
-    # Replace old_str with new_str
-    new_value = current_value.replace(str(old_str), str(new_str))
+    # Replace old_string with new_string
+    new_value = current_value.replace(str(old_string), str(new_string))
 
     # Write the new content to the block
     agent_state.memory.update_block_value(label=label, value=new_value)
 
     # Create a snippet of the edited section
     # SNIPPET_LINES = 3
-    # replacement_line = current_value.split(old_str)[0].count("\n")
+    # replacement_line = current_value.split(old_string)[0].count("\n")
     # start_line = max(0, replacement_line - SNIPPET_LINES)
-    # end_line = replacement_line + SNIPPET_LINES + new_str.count("\n")
+    # end_line = replacement_line + SNIPPET_LINES + new_string.count("\n")
     # snippet = "\n".join(new_value.split("\n")[start_line : end_line + 1])
 
     return new_value
 
 
-def memory_insert(agent_state: "AgentState", label: str, new_str: str, insert_line: int = -1) -> str:  # type: ignore
+def memory_insert(agent_state: "AgentState", label: str, new_string: str, insert_line: int = -1) -> str:  # type: ignore
     """
     The memory_insert command allows you to insert text at a specific location in a memory block.
 
     Args:
         label (str): Section of the memory to be edited, identified by its label.
-        new_str (str): The text to insert. Do not include line number prefixes.
+        new_string (str): The text to insert. Do not include line number prefixes.
         insert_line (int): The line number after which to insert the text (0 for beginning of file). Defaults to -1 (end of the file).
 
     Examples:
         # Update a block containing information about the user (append to the end of the block)
-        memory_insert(label="customer", new_str="The customer's ticket number is 12345")
+        memory_insert(label="customer", new_string="The customer's ticket number is 12345")
 
         # Update a block containing information about the user (insert at the beginning of the block)
-        memory_insert(label="customer", new_str="The customer's ticket number is 12345", insert_line=0)
+        memory_insert(label="customer", new_string="The customer's ticket number is 12345", insert_line=0)
 
     Returns:
         Optional[str]: None is always returned as this function does not produce a response.
     """
     import re
 
-    if bool(re.search(r"\nLine \d+: ", new_str)):
+    if bool(re.search(r"\nLine \d+: ", new_string)):
         raise ValueError(
-            "new_str contains a line number prefix, which is not allowed. Do not include line numbers when calling memory tools (line numbers are for display purposes only)."
+            "new_string contains a line number prefix, which is not allowed. Do not include line numbers when calling memory tools (line numbers are for display purposes only)."
         )
-    if CORE_MEMORY_LINE_NUMBER_WARNING in new_str:
+    if CORE_MEMORY_LINE_NUMBER_WARNING in new_string:
         raise ValueError(
-            "new_str contains a line number warning, which is not allowed. Do not include line number information when calling memory tools (line numbers are for display purposes only)."
+            "new_string contains a line number warning, which is not allowed. Do not include line number information when calling memory tools (line numbers are for display purposes only)."
         )
 
     current_value = str(agent_state.memory.get_block(label).value).expandtabs()
-    new_str = str(new_str).expandtabs()
+    new_string = str(new_string).expandtabs()
     current_value_lines = current_value.split("\n")
     n_lines = len(current_value_lines)
 
@@ -430,11 +432,11 @@ def memory_insert(agent_state: "AgentState", label: str, new_str: str, insert_li
         )
 
     # Insert the new string as a line
-    new_str_lines = new_str.split("\n")
-    new_value_lines = current_value_lines[:insert_line] + new_str_lines + current_value_lines[insert_line:]
+    new_string_lines = new_string.split("\n")
+    new_value_lines = current_value_lines[:insert_line] + new_string_lines + current_value_lines[insert_line:]
     (
         current_value_lines[max(0, insert_line - SNIPPET_LINES) : insert_line]
-        + new_str_lines
+        + new_string_lines
         + current_value_lines[insert_line : insert_line + SNIPPET_LINES]
     )
 

letta/services/tool_executor/core_tool_executor.py

@@ -343,48 +343,55 @@ class LettaCoreToolExecutor(ToolExecutor):
         await self.agent_manager.update_memory_if_changed_async(agent_id=agent_state.id, new_memory=agent_state.memory, actor=actor)
         return new_value
 
-    async def memory_replace(self, agent_state: AgentState, actor: User, label: str, old_str: str, new_str: str) -> str:
+    async def memory_replace(
+        self,
+        agent_state: AgentState,
+        actor: User,
+        label: str,
+        old_string: str,
+        new_string: str,
+    ) -> str:
         if agent_state.memory.get_block(label).read_only:
             raise ValueError(f"{READ_ONLY_BLOCK_EDIT_ERROR}")
 
-        if bool(MEMORY_TOOLS_LINE_NUMBER_PREFIX_REGEX.search(old_str)):
+        if bool(MEMORY_TOOLS_LINE_NUMBER_PREFIX_REGEX.search(old_string)):
             raise ValueError(
-                "old_str contains a line number prefix, which is not allowed. "
+                "old_string contains a line number prefix, which is not allowed. "
                 "Do not include line numbers when calling memory tools (line "
                 "numbers are for display purposes only)."
             )
-        if CORE_MEMORY_LINE_NUMBER_WARNING in old_str:
+        if CORE_MEMORY_LINE_NUMBER_WARNING in old_string:
             raise ValueError(
-                "old_str contains a line number warning, which is not allowed. "
+                "old_string contains a line number warning, which is not allowed. "
                 "Do not include line number information when calling memory tools "
                 "(line numbers are for display purposes only)."
             )
-        if bool(MEMORY_TOOLS_LINE_NUMBER_PREFIX_REGEX.search(new_str)):
+        if bool(MEMORY_TOOLS_LINE_NUMBER_PREFIX_REGEX.search(new_string)):
             raise ValueError(
-                "new_str contains a line number prefix, which is not allowed. "
+                "new_string contains a line number prefix, which is not allowed. "
                 "Do not include line numbers when calling memory tools (line "
                 "numbers are for display purposes only)."
             )
 
-        old_str = str(old_str).expandtabs()
-        new_str = str(new_str).expandtabs()
+        old_string = str(old_string).expandtabs()
+        new_string = str(new_string).expandtabs()
         current_value = str(agent_state.memory.get_block(label).value).expandtabs()
 
-        # Check if old_str is unique in the block
-        occurences = current_value.count(old_str)
+        # Check if old_string is unique in the block
+        occurences = current_value.count(old_string)
         if occurences == 0:
             raise ValueError(
-                f"No replacement was performed, old_str `{old_str}` did not appear verbatim in memory block with label `{label}`."
+                f"No replacement was performed, old_string `{old_string}` did not appear verbatim in memory block with label `{label}`."
             )
         elif occurences > 1:
             content_value_lines = current_value.split("\n")
-            lines = [idx + 1 for idx, line in enumerate(content_value_lines) if old_str in line]
+            lines = [idx + 1 for idx, line in enumerate(content_value_lines) if old_string in line]
             raise ValueError(
-                f"No replacement was performed. Multiple occurrences of old_str `{old_str}` in lines {lines}. Please ensure it is unique."
+                f"No replacement was performed. Multiple occurrences of old_string `{old_string}` in lines {lines}. Please ensure it is unique."
             )
 
-        # Replace old_str with new_str
-        new_value = current_value.replace(str(old_str), str(new_str))
+        # Replace old_string with new_string
+        new_value = current_value.replace(str(old_string), str(new_string))
 
         # Write the new content to the block
         agent_state.memory.update_block_value(label=label, value=new_value)
@@ -678,27 +685,27 @@ class LettaCoreToolExecutor(ToolExecutor):
         agent_state: AgentState,
         actor: User,
         label: str,
-        new_str: str,
+        new_string: str,
         insert_line: int = -1,
     ) -> str:
         if agent_state.memory.get_block(label).read_only:
             raise ValueError(f"{READ_ONLY_BLOCK_EDIT_ERROR}")
 
-        if bool(MEMORY_TOOLS_LINE_NUMBER_PREFIX_REGEX.search(new_str)):
+        if bool(MEMORY_TOOLS_LINE_NUMBER_PREFIX_REGEX.search(new_string)):
             raise ValueError(
-                "new_str contains a line number prefix, which is not allowed. Do not "
+                "new_string contains a line number prefix, which is not allowed. Do not "
                 "include line numbers when calling memory tools (line numbers are for "
                 "display purposes only)."
             )
-        if CORE_MEMORY_LINE_NUMBER_WARNING in new_str:
+        if CORE_MEMORY_LINE_NUMBER_WARNING in new_string:
             raise ValueError(
-                "new_str contains a line number warning, which is not allowed. Do not "
+                "new_string contains a line number warning, which is not allowed. Do not "
                 "include line number information when calling memory tools (line numbers "
                 "are for display purposes only)."
             )
 
         current_value = str(agent_state.memory.get_block(label).value).expandtabs()
-        new_str = str(new_str).expandtabs()
+        new_string = str(new_string).expandtabs()
         current_value_lines = current_value.split("\n")
         n_lines = len(current_value_lines)
 
@@ -714,11 +721,11 @@ class LettaCoreToolExecutor(ToolExecutor):
 
         # Insert the new string as a line
         SNIPPET_LINES = 3
-        new_str_lines = new_str.split("\n")
-        new_value_lines = current_value_lines[:insert_line] + new_str_lines + current_value_lines[insert_line:]
+        new_string_lines = new_string.split("\n")
+        new_value_lines = current_value_lines[:insert_line] + new_string_lines + current_value_lines[insert_line:]
         snippet_lines = (
             current_value_lines[max(0, insert_line - SNIPPET_LINES) : insert_line]
-            + new_str_lines
+            + new_string_lines
             + current_value_lines[insert_line : insert_line + SNIPPET_LINES]
         )
 
@@ -874,7 +881,14 @@ class LettaCoreToolExecutor(ToolExecutor):
             f"Your system prompt has been recompiled with the new memory block and is now active in your context."
         )
 
-    async def memory_str_replace(self, agent_state: AgentState, actor: User, path: str, old_str: str, new_str: str) -> str:
+    async def memory_str_replace(
+        self,
+        agent_state: AgentState,
+        actor: User,
+        path: str,
+        old_string: str,
+        new_string: str,
+    ) -> str:
         """Replace text in a memory block."""
         label = path.removeprefix("/memories/").removeprefix("/")
 
@@ -885,44 +899,44 @@ class LettaCoreToolExecutor(ToolExecutor):
         if memory_block.read_only:
             raise ValueError(f"{READ_ONLY_BLOCK_EDIT_ERROR}")
 
-        if bool(MEMORY_TOOLS_LINE_NUMBER_PREFIX_REGEX.search(old_str)):
+        if bool(MEMORY_TOOLS_LINE_NUMBER_PREFIX_REGEX.search(old_string)):
             raise ValueError(
-                "old_str contains a line number prefix, which is not allowed. "
+                "old_string contains a line number prefix, which is not allowed. "
                 "Do not include line numbers when calling memory tools (line "
                 "numbers are for display purposes only)."
             )
-        if CORE_MEMORY_LINE_NUMBER_WARNING in old_str:
+        if CORE_MEMORY_LINE_NUMBER_WARNING in old_string:
             raise ValueError(
-                "old_str contains a line number warning, which is not allowed. "
+                "old_string contains a line number warning, which is not allowed. "
                 "Do not include line number information when calling memory tools "
                 "(line numbers are for display purposes only)."
             )
-        if bool(MEMORY_TOOLS_LINE_NUMBER_PREFIX_REGEX.search(new_str)):
+        if bool(MEMORY_TOOLS_LINE_NUMBER_PREFIX_REGEX.search(new_string)):
             raise ValueError(
-                "new_str contains a line number prefix, which is not allowed. "
+                "new_string contains a line number prefix, which is not allowed. "
                 "Do not include line numbers when calling memory tools (line "
                 "numbers are for display purposes only)."
             )
 
-        old_str = str(old_str).expandtabs()
-        new_str = str(new_str).expandtabs()
+        old_string = str(old_string).expandtabs()
+        new_string = str(new_string).expandtabs()
         current_value = str(memory_block.value).expandtabs()
 
-        # Check if old_str is unique in the block
-        occurences = current_value.count(old_str)
+        # Check if old_string is unique in the block
+        occurences = current_value.count(old_string)
         if occurences == 0:
             raise ValueError(
-                f"No replacement was performed, old_str `{old_str}` did not appear verbatim in memory block with label `{label}`."
+                f"No replacement was performed, old_string `{old_string}` did not appear verbatim in memory block with label `{label}`."
             )
         elif occurences > 1:
             content_value_lines = current_value.split("\n")
-            lines = [idx + 1 for idx, line in enumerate(content_value_lines) if old_str in line]
+            lines = [idx + 1 for idx, line in enumerate(content_value_lines) if old_string in line]
             raise ValueError(
-                f"No replacement was performed. Multiple occurrences of old_str `{old_str}` in lines {lines}. Please ensure it is unique."
+                f"No replacement was performed. Multiple occurrences of old_string `{old_string}` in lines {lines}. Please ensure it is unique."
             )
 
-        # Replace old_str with new_str
-        new_value = current_value.replace(str(old_str), str(new_str))
+        # Replace old_string with new_string
+        new_value = current_value.replace(str(old_string), str(new_string))
 
         # Write the new content to the block
         await self.block_manager.update_block_async(block_id=memory_block.id, block_update=BlockUpdate(value=new_value), actor=actor)

tests/test_agent_files/deep-thought.af

@@ -276,19 +276,19 @@
               "type": "string",
               "description": "Section of the memory to be edited, identified by its label."
             },
-            "old_str": {
+            "old_string": {
               "type": "string",
               "description": "The text to replace (must match exactly, including whitespace and indentation)."
             },
-            "new_str": {
+            "new_string": {
               "type": "string",
               "description": "The new text to insert in place of the old text. Do not include line number prefixes."
             }
           },
           "required": [
             "label",
-            "old_str",
-            "new_str"
+            "old_string",
+            "new_string"
           ]
         },
         "type": null,
@@ -319,7 +319,7 @@
               "type": "string",
               "description": "Section of the memory to be edited, identified by its label."
             },
-            "new_str": {
+            "new_string": {
               "type": "string",
               "description": "The text to insert. Do not include line number prefixes."
             },
@@ -330,7 +330,7 @@
           },
           "required": [
             "label",
-            "new_str"
+            "new_string"
           ]
         },
         "type": null,

tests/test_agent_files/max_messages.af

@@ -799,7 +799,7 @@
               "type": "string",
               "description": "Section of the memory to be edited, identified by its label."
             },
-            "new_str": {
+            "new_string": {
               "type": "string",
               "description": "The text to insert."
             },
@@ -810,7 +810,7 @@
           },
           "required": [
             "label",
-            "new_str"
+            "new_string"
           ]
         },
         "type": null,
@@ -911,19 +911,19 @@
               "type": "string",
               "description": "Section of the memory to be edited, identified by its label."
             },
-            "old_str": {
+            "old_string": {
               "type": "string",
               "description": "The text to replace (must match exactly, including whitespace and indentation)."
             },
-            "new_str": {
+            "new_string": {
               "type": "string",
               "description": "The new text to insert in place of the old text. Do not include line number prefixes."
             }
           },
           "required": [
             "label",
-            "old_str",
-            "new_str"
+            "old_string",
+            "new_string"
           ]
         },
         "type": null,

tests/test_agent_files/test_agent.af

@@ -1678,7 +1678,7 @@
     {
       "id": "tool-5",
       "tool_type": "letta_memory_core",
-      "description": "Memory management tool with various sub-commands for memory block operations.\n\nExamples:\n        # Replace text in a memory block\n        memory(agent_state, \"str_replace\", path=\"/memories/user_preferences\", old_str=\"theme: dark\", new_str=\"theme: light\")\n\n        # Insert text at line 5\n        memory(agent_state, \"insert\", path=\"/memories/notes\", insert_line=5, insert_text=\"New note here\")\n\n        # Delete a memory block\n        memory(agent_state, \"delete\", path=\"/memories/old_notes\")\n\n        # Rename a memory block\n        memory(agent_state, \"rename\", old_path=\"/memories/temp\", new_path=\"/memories/permanent\")\n\n        # Update the description of a memory block\n        memory(agent_state, \"rename\", path=\"/memories/temp\", description=\"The user's temporary notes.\")\n\n        # Create a memory block with starting text\n        memory(agent_state, \"create\", path=\"/memories/coding_preferences\", \"description\": \"The user's coding preferences.\", \"file_text\": \"The user seems to add type hints to all of their Python code.\")\n\n        # Create an empty memory block\n        memory(agent_state, \"create\", path=\"/memories/coding_preferences\", \"description\": \"The user's coding preferences.\")",
+      "description": "Memory management tool with various sub-commands for memory block operations.\n\nExamples:\n        # Replace text in a memory block\n        memory(agent_state, \"str_replace\", path=\"/memories/user_preferences\", old_string=\"theme: dark\", new_string=\"theme: light\")\n\n        # Insert text at line 5\n        memory(agent_state, \"insert\", path=\"/memories/notes\", insert_line=5, insert_text=\"New note here\")\n\n        # Delete a memory block\n        memory(agent_state, \"delete\", path=\"/memories/old_notes\")\n\n        # Rename a memory block\n        memory(agent_state, \"rename\", old_path=\"/memories/temp\", new_path=\"/memories/permanent\")\n\n        # Update the description of a memory block\n        memory(agent_state, \"rename\", path=\"/memories/temp\", description=\"The user's temporary notes.\")\n\n        # Create a memory block with starting text\n        memory(agent_state, \"create\", path=\"/memories/coding_preferences\", \"description\": \"The user's coding preferences.\", \"file_text\": \"The user seems to add type hints to all of their Python code.\")\n\n        # Create an empty memory block\n        memory(agent_state, \"create\", path=\"/memories/coding_preferences\", \"description\": \"The user's coding preferences.\")",
       "source_type": "python",
       "name": "memory",
       "tags": [
@@ -1687,7 +1687,7 @@
       "source_code": null,
       "json_schema": {
         "name": "memory",
-        "description": "Memory management tool with various sub-commands for memory block operations.\n\nExamples:\n        # Replace text in a memory block\n        memory(agent_state, \"str_replace\", path=\"/memories/user_preferences\", old_str=\"theme: dark\", new_str=\"theme: light\")\n\n        # Insert text at line 5\n        memory(agent_state, \"insert\", path=\"/memories/notes\", insert_line=5, insert_text=\"New note here\")\n\n        # Delete a memory block\n        memory(agent_state, \"delete\", path=\"/memories/old_notes\")\n\n        # Rename a memory block\n        memory(agent_state, \"rename\", old_path=\"/memories/temp\", new_path=\"/memories/permanent\")\n\n        # Update the description of a memory block\n        memory(agent_state, \"rename\", path=\"/memories/temp\", description=\"The user's temporary notes.\")\n\n        # Create a memory block with starting text\n        memory(agent_state, \"create\", path=\"/memories/coding_preferences\", \"description\": \"The user's coding preferences.\", \"file_text\": \"The user seems to add type hints to all of their Python code.\")\n\n        # Create an empty memory block\n        memory(agent_state, \"create\", path=\"/memories/coding_preferences\", \"description\": \"The user's coding preferences.\")",
+        "description": "Memory management tool with various sub-commands for memory block operations.\n\nExamples:\n        # Replace text in a memory block\n        memory(agent_state, \"str_replace\", path=\"/memories/user_preferences\", old_string=\"theme: dark\", new_string=\"theme: light\")\n\n        # Insert text at line 5\n        memory(agent_state, \"insert\", path=\"/memories/notes\", insert_line=5, insert_text=\"New note here\")\n\n        # Delete a memory block\n        memory(agent_state, \"delete\", path=\"/memories/old_notes\")\n\n        # Rename a memory block\n        memory(agent_state, \"rename\", old_path=\"/memories/temp\", new_path=\"/memories/permanent\")\n\n        # Update the description of a memory block\n        memory(agent_state, \"rename\", path=\"/memories/temp\", description=\"The user's temporary notes.\")\n\n        # Create a memory block with starting text\n        memory(agent_state, \"create\", path=\"/memories/coding_preferences\", \"description\": \"The user's coding preferences.\", \"file_text\": \"The user seems to add type hints to all of their Python code.\")\n\n        # Create an empty memory block\n        memory(agent_state, \"create\", path=\"/memories/coding_preferences\", \"description\": \"The user's coding preferences.\")",
         "parameters": {
           "type": "object",
           "properties": {
@@ -1707,11 +1707,11 @@
               "type": "string",
               "description": "The description to set in the memory block (for create, rename)"
             },
-            "old_str": {
+            "old_string": {
               "type": "string",
               "description": "Old text to replace (for str_replace)"
             },
-            "new_str": {
+            "new_string": {
               "type": "string",
               "description": "New text to replace with (for str_replace)"
             },

tests/test_agent_files/test_agent_with_files_and_sources.af

@@ -514,7 +514,7 @@
               "type": "string",
               "description": "Section of the memory to be edited, identified by its label."
             },
-            "new_str": {
+            "new_string": {
               "type": "string",
               "description": "The text to insert. Do not include line number prefixes."
             },
@@ -525,7 +525,7 @@
           },
           "required": [
             "label",
-            "new_str"
+            "new_string"
           ]
         }
       },
@@ -557,19 +557,19 @@
               "type": "string",
               "description": "Section of the memory to be edited, identified by its label."
             },
-            "old_str": {
+            "old_string": {
               "type": "string",
               "description": "The text to replace (must match exactly, including whitespace and indentation)."
             },
-            "new_str": {
+            "new_string": {
               "type": "string",
               "description": "The new text to insert in place of the old text. Do not include line number prefixes."
             }
           },
           "required": [
             "label",
-            "old_str",
-            "new_str"
+            "old_string",
+            "new_string"
           ]
         }
       },

tests/test_agent_files/test_basic_agent_with_blocks_tools_messages_v2.af

@@ -574,7 +574,7 @@
     {
       "id": "tool-6",
       "tool_type": "letta_sleeptime_core",
-      "description": "The memory_insert command allows you to insert text at a specific location in a memory block.\n\nExamples:\n        # Update a block containing information about the user (append to the end of the block)\n        memory_insert(label=\"customer\", new_str=\"The customer's ticket number is 12345\")\n\n        # Update a block containing information about the user (insert at the beginning of the block)\n        memory_insert(label=\"customer\", new_str=\"The customer's ticket number is 12345\", insert_line=0)\n\n    Returns:\n        Optional[str]: None is always returned as this function does not produce a response.",
+      "description": "The memory_insert command allows you to insert text at a specific location in a memory block.\n\nExamples:\n        # Update a block containing information about the user (append to the end of the block)\n        memory_insert(label=\"customer\", new_string=\"The customer's ticket number is 12345\")\n\n        # Update a block containing information about the user (insert at the beginning of the block)\n        memory_insert(label=\"customer\", new_string=\"The customer's ticket number is 12345\", insert_line=0)\n\n    Returns:\n        Optional[str]: None is always returned as this function does not produce a response.",
       "source_type": "python",
       "name": "memory_insert",
       "tags": [
@@ -583,7 +583,7 @@
       "source_code": null,
       "json_schema": {
         "name": "memory_insert",
-        "description": "The memory_insert command allows you to insert text at a specific location in a memory block.\n\nExamples:\n        # Update a block containing information about the user (append to the end of the block)\n        memory_insert(label=\"customer\", new_str=\"The customer's ticket number is 12345\")\n\n        # Update a block containing information about the user (insert at the beginning of the block)\n        memory_insert(label=\"customer\", new_str=\"The customer's ticket number is 12345\", insert_line=0)\n\n    Returns:\n        Optional[str]: None is always returned as this function does not produce a response.",
+        "description": "The memory_insert command allows you to insert text at a specific location in a memory block.\n\nExamples:\n        # Update a block containing information about the user (append to the end of the block)\n        memory_insert(label=\"customer\", new_string=\"The customer's ticket number is 12345\")\n\n        # Update a block containing information about the user (insert at the beginning of the block)\n        memory_insert(label=\"customer\", new_string=\"The customer's ticket number is 12345\", insert_line=0)\n\n    Returns:\n        Optional[str]: None is always returned as this function does not produce a response.",
         "parameters": {
           "type": "object",
           "properties": {
@@ -591,7 +591,7 @@
               "type": "string",
               "description": "Section of the memory to be edited, identified by its label."
             },
-            "new_str": {
+            "new_string": {
               "type": "string",
               "description": "The text to insert. Do not include line number prefixes."
             },
@@ -602,7 +602,7 @@
           },
           "required": [
             "label",
-            "new_str"
+            "new_string"
           ]
         }
       },
@@ -618,7 +618,7 @@
     {
       "id": "tool-1",
       "tool_type": "letta_sleeptime_core",
-      "description": "The memory_replace command allows you to replace a specific string in a memory block with a new string. This is used for making precise edits.\n\nExamples:\n        # Update a block containing information about the user\n        memory_replace(label=\"human\", old_str=\"Their name is Alice\", new_str=\"Their name is Bob\")\n\n        # Update a block containing a todo list\n        memory_replace(label=\"todos\", old_str=\"- [ ] Step 5: Search the web\", new_str=\"- [x] Step 5: Search the web\")\n\n        # Pass an empty string to\n        memory_replace(label=\"human\", old_str=\"Their name is Alice\", new_str=\"\")\n\n        # Bad example - do NOT add (view-only) line numbers to the args\n        memory_replace(label=\"human\", old_str=\"Line 1: Their name is Alice\", new_str=\"Line 1: Their name is Bob\")\n\n        # Bad example - do NOT include the number number warning either\n        memory_replace(label=\"human\", old_str=\"# NOTE: Line numbers shown below are to help during editing. Do NOT include line number prefixes in your memory edit tool calls.\\nLine 1: Their name is Alice\", new_str=\"Line 1: Their name is Bob\")\n\n        # Good example - no line numbers or line number warning (they are view-only), just the text\n        memory_replace(label=\"human\", old_str=\"Their name is Alice\", new_str=\"Their name is Bob\")\n\n    Returns:\n        str: The success message",
+      "description": "The memory_replace command allows you to replace a specific string in a memory block with a new string. This is used for making precise edits.\n\nExamples:\n        # Update a block containing information about the user\n        memory_replace(label=\"human\", old_string=\"Their name is Alice\", new_string=\"Their name is Bob\")\n\n        # Update a block containing a todo list\n        memory_replace(label=\"todos\", old_string=\"- [ ] Step 5: Search the web\", new_string=\"- [x] Step 5: Search the web\")\n\n        # Pass an empty string to\n        memory_replace(label=\"human\", old_string=\"Their name is Alice\", new_string=\"\")\n\n        # Bad example - do NOT add (view-only) line numbers to the args\n        memory_replace(label=\"human\", old_string=\"Line 1: Their name is Alice\", new_string=\"Line 1: Their name is Bob\")\n\n        # Bad example - do NOT include the number number warning either\n        memory_replace(label=\"human\", old_string=\"# NOTE: Line numbers shown below are to help during editing. Do NOT include line number prefixes in your memory edit tool calls.\\nLine 1: Their name is Alice\", new_string=\"Line 1: Their name is Bob\")\n\n        # Good example - no line numbers or line number warning (they are view-only), just the text\n        memory_replace(label=\"human\", old_string=\"Their name is Alice\", new_string=\"Their name is Bob\")\n\n    Returns:\n        str: The success message",
       "source_type": "python",
       "name": "memory_replace",
       "tags": [
@@ -627,7 +627,7 @@
       "source_code": null,
       "json_schema": {
         "name": "memory_replace",
-        "description": "The memory_replace command allows you to replace a specific string in a memory block with a new string. This is used for making precise edits.\n\nExamples:\n        # Update a block containing information about the user\n        memory_replace(label=\"human\", old_str=\"Their name is Alice\", new_str=\"Their name is Bob\")\n\n        # Update a block containing a todo list\n        memory_replace(label=\"todos\", old_str=\"- [ ] Step 5: Search the web\", new_str=\"- [x] Step 5: Search the web\")\n\n        # Pass an empty string to\n        memory_replace(label=\"human\", old_str=\"Their name is Alice\", new_str=\"\")\n\n        # Bad example - do NOT add (view-only) line numbers to the args\n        memory_replace(label=\"human\", old_str=\"Line 1: Their name is Alice\", new_str=\"Line 1: Their name is Bob\")\n\n        # Bad example - do NOT include the number number warning either\n        memory_replace(label=\"human\", old_str=\"# NOTE: Line numbers shown below are to help during editing. Do NOT include line number prefixes in your memory edit tool calls.\\nLine 1: Their name is Alice\", new_str=\"Line 1: Their name is Bob\")\n\n        # Good example - no line numbers or line number warning (they are view-only), just the text\n        memory_replace(label=\"human\", old_str=\"Their name is Alice\", new_str=\"Their name is Bob\")\n\n    Returns:\n        str: The success message",
+        "description": "The memory_replace command allows you to replace a specific string in a memory block with a new string. This is used for making precise edits.\n\nExamples:\n        # Update a block containing information about the user\n        memory_replace(label=\"human\", old_string=\"Their name is Alice\", new_string=\"Their name is Bob\")\n\n        # Update a block containing a todo list\n        memory_replace(label=\"todos\", old_string=\"- [ ] Step 5: Search the web\", new_string=\"- [x] Step 5: Search the web\")\n\n        # Pass an empty string to\n        memory_replace(label=\"human\", old_string=\"Their name is Alice\", new_string=\"\")\n\n        # Bad example - do NOT add (view-only) line numbers to the args\n        memory_replace(label=\"human\", old_string=\"Line 1: Their name is Alice\", new_string=\"Line 1: Their name is Bob\")\n\n        # Bad example - do NOT include the number number warning either\n        memory_replace(label=\"human\", old_string=\"# NOTE: Line numbers shown below are to help during editing. Do NOT include line number prefixes in your memory edit tool calls.\\nLine 1: Their name is Alice\", new_string=\"Line 1: Their name is Bob\")\n\n        # Good example - no line numbers or line number warning (they are view-only), just the text\n        memory_replace(label=\"human\", old_string=\"Their name is Alice\", new_string=\"Their name is Bob\")\n\n    Returns:\n        str: The success message",
         "parameters": {
           "type": "object",
           "properties": {
@@ -635,19 +635,19 @@
               "type": "string",
               "description": "Section of the memory to be edited, identified by its label."
             },
-            "old_str": {
+            "old_string": {
               "type": "string",
               "description": "The text to replace (must match exactly, including whitespace and indentation)."
             },
-            "new_str": {
+            "new_string": {
               "type": "string",
               "description": "The new text to insert in place of the old text. Do not include line number prefixes."
             }
           },
           "required": [
             "label",
-            "old_str",
-            "new_str"
+            "old_string",
+            "new_string"
           ]
         }
       },

tests/test_sdk_client.py

@@ -2438,7 +2438,7 @@ def test_calling_tools(client: LettaSDKClient, agent: AgentState) -> None:
     assert len(blocks) == 1, f"Expected 1 block, got {len(blocks)}"
 
     # test calling a stateful tool
-    result = client.agents.tools.run(agent_id=agent.id, tool_name="memory_insert", args={"label": "human", "new_str": "test"})
+    result = client.agents.tools.run(agent_id=agent.id, tool_name="memory_insert", args={"label": "human", "new_string": "test"})
     assert result.status == "success", f"Expected success, got {result.status}"
     # get the block
     block = client.agents.blocks.retrieve(agent_id=agent.id, block_label="human")