fix(eval): guard resource-read tool field against non-hashable values

The telemetry parser crashed when an MCP tool-call event carried a
non-string `tool` field (e.g. a list). Check the type before membership
testing against `_RESOURCE_READ_TOOL_NAMES` so malformed events are
skipped instead of raising.

Generated with [Devin](https://devin.ai)

Co-Authored-By: Devin <158243242+devin-ai-integration[bot]@users.noreply.github.com>

Author: morluto

tests/unit/tooling/test_eval_telemetry.py

@@ -427,3 +427,38 @@ def link_event(link_uri: str) -> dict[str, object]:
     assert telemetry["mcp_resource_uri_preservation_attempts"] == 3
     assert telemetry["mcp_resource_uri_preservation_successes"] == 2
     assert telemetry["mcp_resource_digest_preservation_successes"] == 2
+
+
+def test_agent_telemetry_handles_non_hashable_resource_tool_field(tmp_path: Path) -> None:
+    uri = "artifact://sha256/" + ("f" * 64)
+    malformed_tool_event = {
+        "type": "item.completed",
+        "item": {
+            "type": "mcp_tool_call",
+            "tool": ["resources", "read"],
+            "status": "completed",
+            "arguments": {"uri": uri},
+            "result": {"isError": False, "content": []},
+        },
+    }
+    valid_read = _tool_event(
+        "resources/read",
+        {"uri": uri},
+        {
+            "artifact_uri": uri,
+            "manifest": {"payload_digest": "sha256:" + ("e" * 64)},
+            "payload": {},
+        },
+    )
+    transcript = tmp_path / "transcript.jsonl"
+    transcript.write_text(
+        "\n".join(json.dumps(event) for event in (malformed_tool_event, valid_read))
+        + "\n",
+        encoding="utf-8",
+    )
+
+    telemetry = parse_agent_transcript(transcript)
+
+    assert telemetry["mcp_resource_read_attempts"] == 1
+    assert telemetry["mcp_resource_read_uris"] == [uri]
+    assert telemetry["mcp_resource_read_successes"] == 1