refactor: break up delegate_to_kimi into helpers

Extract _find_kimi_cli, _resolve_workdir, and _run_kimi from the 68-line
delegate_to_kimi function, reducing it to ~15 lines.

Fixes #635

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

src/timmy/tools_delegation/__init__.py

@@ -89,52 +89,41 @@ def list_swarm_agents() -> dict[str, Any]:
         }
 
 
-def delegate_to_kimi(task: str, working_directory: str = "") -> dict[str, Any]:
-    """Delegate a coding task to Kimi, the external coding agent.
-
-    Kimi has 262K context and is optimized for code tasks: writing,
-    debugging, refactoring, test writing. Timmy thinks and plans,
-    Kimi executes bulk code changes.
-
-    Args:
-        task: Clear, specific coding task description. Include file paths
-              and expected behavior. Good: "Fix the bug in src/timmy/session.py
-              where sessions don't persist." Bad: "Fix all bugs."
-        working_directory: Directory for Kimi to work in. Defaults to repo root.
-
-    Returns:
-        Dict with success status and Kimi's output or error.
-    """
+def _find_kimi_cli() -> str | None:
+    """Return the path to the kimi CLI, or None if not installed."""
     import shutil
-    import subprocess
+
+    return shutil.which("kimi")
+
+
+def _resolve_workdir(working_directory: str) -> str | dict[str, Any]:
+    """Resolve and validate the working directory.
+
+    Returns the resolved path string, or an error dict if invalid.
+    """
     from pathlib import Path
 
     from config import settings
 
-    kimi_path = shutil.which("kimi")
-    if not kimi_path:
-        return {
-            "success": False,
-            "error": "kimi CLI not found on PATH. Install with: pip install kimi-cli",
-        }
-
     workdir = working_directory or settings.repo_root
     if not Path(workdir).is_dir():
         return {
             "success": False,
             "error": f"Working directory does not exist: {workdir}",
         }
+    return workdir
 
-    cmd = [kimi_path, "--print", "-p", task]
 
-    logger.info("Delegating to Kimi: %s (cwd=%s)", task[:80], workdir)
+def _run_kimi(cmd: list[str], workdir: str) -> dict[str, Any]:
+    """Execute the kimi subprocess and return a result dict."""
+    import subprocess
 
     try:
         result = subprocess.run(
             cmd,
             capture_output=True,
             text=True,
-            timeout=300,  # 5 minute timeout for coding tasks
+            timeout=300,
             cwd=workdir,
         )
 
@@ -157,3 +146,34 @@ def delegate_to_kimi(task: str, working_directory: str = "") -> dict[str, Any]:
             "success": False,
             "error": f"Failed to run Kimi: {exc}",
         }
+
+
+def delegate_to_kimi(task: str, working_directory: str = "") -> dict[str, Any]:
+    """Delegate a coding task to Kimi, the external coding agent.
+
+    Kimi has 262K context and is optimized for code tasks: writing,
+    debugging, refactoring, test writing. Timmy thinks and plans,
+    Kimi executes bulk code changes.
+
+    Args:
+        task: Clear, specific coding task description. Include file paths
+              and expected behavior. Good: "Fix the bug in src/timmy/session.py
+              where sessions don't persist." Bad: "Fix all bugs."
+        working_directory: Directory for Kimi to work in. Defaults to repo root.
+
+    Returns:
+        Dict with success status and Kimi's output or error.
+    """
+    kimi_path = _find_kimi_cli()
+    if not kimi_path:
+        return {
+            "success": False,
+            "error": "kimi CLI not found on PATH. Install with: pip install kimi-cli",
+        }
+
+    workdir = _resolve_workdir(working_directory)
+    if isinstance(workdir, dict):
+        return workdir
+
+    logger.info("Delegating to Kimi: %s (cwd=%s)", task[:80], workdir)
+    return _run_kimi([kimi_path, "--print", "-p", task], workdir)