extract parser.py and tool_runner.py from agent code

agents/shared/parser.py

@@ -0,0 +1,56 @@
+"""Parsers for MCP response content (tools, resources, prompts)."""
+
+import json
+from typing import Any
+
+
+def _extract_texts(result: Any) -> list[str]:
+    """Pull text fields out of an MCP response, handling list/content/str shapes."""
+    if isinstance(result, list):
+        return [c.text for c in result if hasattr(c, "text")]
+    if hasattr(result, "content"):
+        return [c.text for c in result.content if hasattr(c, "text")]
+    return []
+
+
+def _maybe_json(text: str) -> Any:
+    """Parse JSON if possible; fall back to raw text."""
+    try:
+        return json.loads(text)
+    except (json.JSONDecodeError, TypeError):
+        return text
+
+
+def parse_tool_result(result: Any) -> Any:
+    """Parse `client.call_tool()` result into native Python structure."""
+    texts = _extract_texts(result)
+    if not texts:
+        return result
+    if len(texts) == 1:
+        return _maybe_json(texts[0])
+    return [_maybe_json(t) for t in texts]
+
+
+def parse_resource_result(result: Any) -> Any:
+    """Parse `client.read_resource()` result — often a JSON-encoded string."""
+    if isinstance(result, str):
+        return _maybe_json(result)
+    return result
+
+
+def parse_prompt_result(result: Any) -> str:
+    """Flatten a prompt response into a single string."""
+    if isinstance(result, str):
+        return result
+    if not hasattr(result, "messages"):
+        return str(result)
+
+    texts: list[str] = []
+    for msg in result.messages:
+        if hasattr(msg.content, "text"):
+            texts.append(msg.content.text)
+        elif isinstance(msg.content, list):
+            for c in msg.content:
+                if hasattr(c, "text"):
+                    texts.append(c.text)
+    return "\n".join(texts) if texts else str(result)