diff --git a/.gitignore b/.gitignore
index b43656d722..0016d0def2 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1,6 +1,7 @@
 # Dependencies
 .sisyphus/
 node_modules/
+__pycache__
 
 # Build output
 dist/
@@ -18,6 +19,7 @@ Thumbs.db
 # Logs
 *.log
 npm-debug.log*
+jobs
 
 # Lock files (use bun.lockb instead)
 package-lock.json
diff --git a/benchmark/__init__.py b/benchmark/__init__.py
new file mode 100644
index 0000000000..e69de29bb2
diff --git a/benchmark/install-sisyphus.sh.j2 b/benchmark/install-sisyphus.sh.j2
new file mode 100644
index 0000000000..f323353301
--- /dev/null
+++ b/benchmark/install-sisyphus.sh.j2
@@ -0,0 +1,46 @@
+#!/bin/bash
+set -e
+
+apt-get update
+apt-get install -y curl unzip
+
+# Install bun
+curl -fsSL https://bun.sh/install | bash
+export BUN_INSTALL="$HOME/.bun"
+export PATH="$BUN_INSTALL/bin:$PATH"
+bun --version
+
+# Install OpenCode
+{% if version %}
+bun install -g opencode-ai@{{ version }}
+{% else %}
+bun install -g opencode-ai@latest
+{% endif %}
+
+# Pre-create oh-my-opencode config BEFORE install to disable problematic hooks
+# This prevents hooks from initializing during plugin load
+# - comment-checker: Downloads Go binary from GitHub (rate limiting with multiple containers)
+# - auto-update-checker: Checks for updates (unnecessary in benchmarks)
+# - session-notification: OS notifications (no display in containers)
+# - background-notification: OS notifications (no display in containers)
+mkdir -p ~/.config/opencode
+cat > ~/.config/opencode/oh-my-opencode.json << 'EOF'
+{
+  "disabled_hooks": [
+    "auto-update-checker",
+    "session-notification",
+    "background-notification"
+  ]
+}
+EOF
+
+# Install oh-my-opencode plugin (provides Sisyphus agent)
+# --claude=no uses opencode/zen provider (free) instead of Anthropic
+{% if omo_version %}
+bunx oh-my-opencode@{{ omo_version }} install --no-tui --claude=no --chatgpt=no --gemini=no
+{% else %}
+bunx oh-my-opencode@latest install --no-tui --claude=no --chatgpt=no --gemini=no
+{% endif %}
+
+opencode --version
+echo "Sisyphus agent ready"
diff --git a/benchmark/sisyphus_agent.py b/benchmark/sisyphus_agent.py
new file mode 100644
index 0000000000..efbf42abf0
--- /dev/null
+++ b/benchmark/sisyphus_agent.py
@@ -0,0 +1,83 @@
+import os
+import shlex
+from pathlib import Path
+
+from harbor.agents.installed.base import BaseInstalledAgent, ExecInput
+from harbor.models.agent.context import AgentContext
+
+
+class SisyphusAgent(BaseInstalledAgent):
+    """
+    Sisyphus agent uses OpenCode with oh-my-opencode plugin.
+    """
+
+    @staticmethod
+    def name() -> str:
+        return "sisyphus"
+
+    @property
+    def _install_agent_template_path(self) -> Path:
+        return Path(__file__).parent / "install-sisyphus.sh.j2"
+
+    def populate_context_post_run(self, context: AgentContext) -> None:
+        pass
+
+    def create_run_agent_commands(self, instruction: str) -> list[ExecInput]:
+        escaped_instruction = shlex.quote(instruction)
+
+        if not self.model_name or "/" not in self.model_name:
+            raise ValueError("Model name must be in the format provider/model_name")
+
+        provider, _ = self.model_name.split("/", 1)
+
+        env = self._get_provider_env(provider)
+        env["OPENCODE_FAKE_VCS"] = "git"
+
+        return [
+            ExecInput(
+                command=(
+                    f"opencode --model {self.model_name} run "
+                    f"--agent Sisyphus --format=json {escaped_instruction} "
+                    f"2>&1 | tee /logs/agent/sisyphus.txt"
+                ),
+                env=env,
+            )
+        ]
+
+    def _get_provider_env(self, provider: str) -> dict[str, str]:
+        env = {}
+        provider_keys = {
+            "amazon-bedrock": [
+                "AWS_ACCESS_KEY_ID",
+                "AWS_SECRET_ACCESS_KEY",
+                "AWS_REGION",
+            ],
+            "anthropic": ["ANTHROPIC_API_KEY"],
+            "azure": ["AZURE_RESOURCE_NAME", "AZURE_API_KEY"],
+            "deepseek": ["DEEPSEEK_API_KEY"],
+            "github-copilot": ["GITHUB_TOKEN"],
+            "google": [
+                "GEMINI_API_KEY",
+                "GOOGLE_GENERATIVE_AI_API_KEY",
+                "GOOGLE_APPLICATION_CREDENTIALS",
+                "GOOGLE_CLOUD_PROJECT",
+                "GOOGLE_CLOUD_LOCATION",
+                "GOOGLE_GENAI_USE_VERTEXAI",
+                "GOOGLE_API_KEY",
+            ],
+            "groq": ["GROQ_API_KEY"],
+            "huggingface": ["HF_TOKEN"],
+            "llama": ["LLAMA_API_KEY"],
+            "mistral": ["MISTRAL_API_KEY"],
+            "openai": ["OPENAI_API_KEY"],
+            "opencode": [],  # opencode/zen - no API key required
+            "xai": ["XAI_API_KEY"],
+        }
+
+        keys = provider_keys.get(provider, [])
+
+        for key in keys:
+            if key in os.environ:
+                env[key] = os.environ[key]
+
+        return env