From ec9b96a7bf5496a67b9449c5da6592839c808fe1 Mon Sep 17 00:00:00 2001
From: Drew Ritter <drew@primeradiant.com>
Date: Wed, 6 May 2026 15:09:59 -0700
Subject: [PATCH] evals: add Gemini 2.5 Flash backend

---
 evals/README.md                      |  3 ++-
 evals/backends/gemini-2-5-flash.yaml | 23 +++++++++++++++++++++++
 evals/backends/gemini.yaml           |  2 +-
 evals/tests/test_backend.py          | 11 +++++++++++
 4 files changed, 37 insertions(+), 2 deletions(-)
 create mode 100644 evals/backends/gemini-2-5-flash.yaml

diff --git a/evals/README.md b/evals/README.md
index c74985ae..1a97d60a 100644
--- a/evals/README.md
+++ b/evals/README.md
@@ -64,7 +64,8 @@ uv run drill list
 | `claude-opus-4-6-1m` | Claude Code | opus-4-6 (1M context) |
 | `claude-opus-4-7-1m` | Claude Code | opus-4-7 (1M context) |
 | `codex` | Codex CLI | — |
-| `gemini` | Gemini CLI | — |
+| `gemini` | Gemini CLI | auto-gemini-3 |
+| `gemini-2-5-flash` | Gemini CLI | gemini-2.5-flash |
 
 ## Project structure
 
diff --git a/evals/backends/gemini-2-5-flash.yaml b/evals/backends/gemini-2-5-flash.yaml
new file mode 100644
index 00000000..7a4e7218
--- /dev/null
+++ b/evals/backends/gemini-2-5-flash.yaml
@@ -0,0 +1,23 @@
+name: gemini-2-5-flash
+cli: gemini
+args:
+  - "--yolo"
+  - "-m"
+  - "gemini-2.5-flash"
+required_env: []
+hooks:
+  pre_run:
+    - link_gemini_extension
+  post_run: []
+shutdown: "/exit"
+idle:
+  quiescence_seconds: 5
+  ready_pattern: "Type your message|^\\s*>"
+busy_pattern: "Thinking\\.\\.\\.|Executing"
+startup_timeout: 60
+turn_timeout: 300
+terminal:
+  cols: 200
+  rows: 50
+session_logs:
+  pattern: "~/.gemini/tmp/*/chats/session-*.json"
diff --git a/evals/backends/gemini.yaml b/evals/backends/gemini.yaml
index 252c5efe..54d0979d 100644
--- a/evals/backends/gemini.yaml
+++ b/evals/backends/gemini.yaml
@@ -3,7 +3,7 @@ cli: gemini
 args:
   - "--yolo"
   - "-m"
-  - "gemini-2.5-flash"
+  - "auto-gemini-3"
 required_env: []
 hooks:
   pre_run:
diff --git a/evals/tests/test_backend.py b/evals/tests/test_backend.py
index ac1d0343..f84742a1 100644
--- a/evals/tests/test_backend.py
+++ b/evals/tests/test_backend.py
@@ -33,6 +33,17 @@ class TestLoadBackend:
         assert backend.family == "claude"
         assert backend.model == "claude-opus-4-6"
 
+    def test_loads_gemini_default_and_flash_variant(self, backends_dir):
+        backend = load_backend("gemini", backends_dir)
+        assert backend.name == "gemini"
+        assert backend.family == "gemini"
+        assert backend.model == "auto-gemini-3"
+
+        flash_backend = load_backend("gemini-2-5-flash", backends_dir)
+        assert flash_backend.name == "gemini-2-5-flash"
+        assert flash_backend.family == "gemini"
+        assert flash_backend.model == "gemini-2.5-flash"
+
 
 class TestBackendBuildCommand:
     def test_claude_build_command(self, backends_dir, monkeypatch):