add new InsertAfterSubstringTool

Unfortunately LLMs can't count line numbers so when they insert new
'Patch' lines, they make mistakes easily.

This new tool should make the 'Patch' line addition more deterministic.

Example:
```
"input": {
  "file": "/git-repos/RHEL-107890/apr/apr.spec",
  "insert_after_substring": "Patch4: apr-1.7.2-autoconf.patch",
  "new_string": "Patch5: RHEL-107890.patch"
},
"output": "Successfully inserted the specified text into /git-repos/RHEL-107890/apr/apr.spec"
```

Signed-off-by: Tomas Tomecek <[email protected]>
Assisted-by: Cursor(Claude)
Co-authored-by: gemini-code-assist[bot] <176961590+gemini-code-assist[bot]@users.noreply.github.com>

Author: TomasTomecek

beeai/agents/backport_agent.py

@@ -33,7 +33,7 @@
 from observability import setup_observability
 from tools.commands import RunShellCommandTool
 from tools.specfile import AddChangelogEntryTool, BumpReleaseTool
-from tools.text import CreateTool, InsertTool, StrReplaceTool, ViewTool
+from tools.text import CreateTool, InsertAfterSubstringTool, InsertTool, StrReplaceTool, ViewTool
 from tools.wicked_git import GitLogSearchTool, GitPatchCreationTool, GitPreparePackageSources
 from triage_agent import BackportData, ErrorData
 from utils import check_subprocess, get_agent_execution_config, mcp_tools, render_prompt
@@ -113,6 +113,7 @@ def create_backport_agent(_: list[Tool], run_shell_command_options: dict[str, An
             CreateTool(),
             ViewTool(),
             InsertTool(),
+            InsertAfterSubstringTool(),
             StrReplaceTool(),
             GitPatchCreationTool(),
             GitLogSearchTool(),

beeai/agents/rebase_agent.py

@@ -32,7 +32,7 @@
 from observability import setup_observability
 from tools.commands import RunShellCommandTool
 from tools.specfile import AddChangelogEntryTool
-from tools.text import CreateTool, InsertTool, StrReplaceTool, ViewTool
+from tools.text import CreateTool, InsertAfterSubstringTool, InsertTool, StrReplaceTool, ViewTool
 from triage_agent import RebaseData, ErrorData
 from utils import get_agent_execution_config, mcp_tools, render_prompt, run_tool
 
@@ -127,6 +127,7 @@ def create_rebase_agent(mcp_tools: list[Tool], run_shell_command_options: dict[s
             CreateTool(),
             ViewTool(),
             InsertTool(),
+            InsertAfterSubstringTool(),
             StrReplaceTool(),
             AddChangelogEntryTool(),
         ] + [t for t in mcp_tools if t.name == "upload_sources"],

beeai/agents/tests/unit/test_tools.py

@@ -2,6 +2,7 @@
 import subprocess
 from textwrap import dedent
 
+from beeai_framework.tools import ToolError
 import pytest
 from flexmock import flexmock
 from specfile import specfile
@@ -26,6 +27,8 @@
 from tools.text import (
     CreateTool,
     CreateToolInput,
+    InsertAfterSubstringTool,
+    InsertAfterSubstringToolInput,
     ViewTool,
     ViewToolInput,
     InsertTool,
@@ -265,6 +268,49 @@ async def test_insert(line, content, tmp_path):
     assert test_file.read_text() == content
 
 
+@pytest.mark.parametrize(
+    "insert_after_substring, final_content",
+    [
+        (
+            "Line 1",
+            "Line 1\nInserted line\nLine 2\nLine 3\n",
+        ),
+        (
+            "Line 2",
+            "Line 1\nLine 2\nInserted line\nLine 3\n",
+        ),
+        (
+            "Line 3",
+            "Line 1\nLine 2\nLine 3\nInserted line\n",
+        ),
+    ],
+)
+@pytest.mark.asyncio
+async def test_insert_after_substring(insert_after_substring, final_content, tmp_path):
+    test_file = tmp_path / "test.txt"
+    test_file.write_text("Line 1\nLine 2\nLine 3\n")
+    tool = InsertAfterSubstringTool()
+    output = await tool.run(
+        input=InsertAfterSubstringToolInput(file=test_file, insert_after_substring=insert_after_substring, new_string="Inserted line")
+    ).middleware(GlobalTrajectoryMiddleware(pretty=True))
+    result = output.result
+    assert result.startswith("Successfully")
+    assert test_file.read_text() == final_content
+
+
+@pytest.mark.asyncio
+async def test_insert_after_substring_missing(tmp_path):
+    test_file = tmp_path / "test.txt"
+    test_file.write_text("Line 1\nLine 2\nLine 3\n")
+    tool = InsertAfterSubstringTool()
+    with pytest.raises(ToolError) as e:
+        await tool.run(
+            input=InsertAfterSubstringToolInput(file=test_file, insert_after_substring="Line 4", new_string="Inserted line")
+        ).middleware(GlobalTrajectoryMiddleware(pretty=True))
+    result = e.value.message
+    assert "No insertion was done because the specified substring wasn't present" in result
+
+
 @pytest.mark.asyncio
 async def test_str_replace(tmp_path):
     test_file = tmp_path / "test.txt"

beeai/agents/tools/text.py

@@ -89,7 +89,7 @@ class InsertToolInput(BaseModel):
 class InsertTool(Tool[InsertToolInput, ToolRunOptions, StringToolOutput]):
     name = "insert"
     description = """
-    Inserts the specified text at a specific location in a file.
+    Inserts the specified text at a specific location in a file
     """
     input_schema = InsertToolInput
 
@@ -111,6 +111,51 @@ async def _run(
         return StringToolOutput(result=f"Successfully inserted the specified text into {tool_input.file}")
 
 
+class InsertAfterSubstringToolInput(BaseModel):
+    file: AbsolutePath = Field(description="Absolute path to a file to edit")
+    insert_after_substring: str = Field(description="Substring to insert the text after")
+    new_string: str = Field(description="Text to insert")
+
+
+class InsertAfterSubstringTool(Tool[InsertAfterSubstringToolInput, ToolRunOptions, StringToolOutput]):
+    name = "insert_after_substring"
+    description = """
+    Inserts the provided text new_string on a new line after the first
+    occurrence of the specified substring insert_after_substring. The insertion
+    happens only once.
+    """
+    input_schema = InsertAfterSubstringToolInput
+
+    def _create_emitter(self) -> Emitter:
+        return Emitter.root().child(
+            namespace=["tool", "text", self.name],
+            creator=self,
+        )
+
+    async def _run(
+        self, tool_input: InsertAfterSubstringToolInput, options: ToolRunOptions | None, context: RunContext
+    ) -> StringToolOutput:
+        if not tool_input.insert_after_substring:
+            raise ToolError("No insertion was done because the specified substring wasn't provided")
+        try:
+            content = await asyncio.to_thread(tool_input.file.read_text)
+            if tool_input.insert_after_substring not in content:
+                raise ToolError("No insertion was done because the specified substring wasn't present")
+            await asyncio.to_thread(
+                tool_input.file.write_text,
+                content.replace(
+                    tool_input.insert_after_substring,
+                    tool_input.insert_after_substring + "\n" + tool_input.new_string,
+                    1  # Replace only the first occurrence, 'count' kw introduced in Python 3.13
+                )
+            )
+        except ToolError:
+            raise
+        except Exception as e:
+            raise ToolError(f"Failed to insert text: {e}") from e
+        return StringToolOutput(result=f"Successfully inserted the specified text into {tool_input.file}")
+
+
 class StrReplaceToolInput(BaseModel):
     file: AbsolutePath = Field(description="Absolute path to a file to edit")
     old_string: str = Field(