1 files changed, 25 insertions, 0 deletions
diff --git a/internal/sandbox/sandbox.go b/internal/sandbox/sandbox.go
new file mode 100644
index 0000000..4275475
--- /dev/null
+++ b/internal/sandbox/sandbox.go
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+// Package sandbox defines the filesystem/shell/git surface an agent loop
+// executes tool calls against. Sandbox is intentionally narrow — just the
+// operations internal/agentloop's read_file/write_file/run_bash/glob tools
+// and its git clone/push/cleanup lifecycle need.
+//
+// Phase 1 ships exactly one implementation, HostSandbox, which lifts the
+// LocalRunner's existing behavior (host git clone into a temp dir, plain
+// os.Exec-backed file/bash tools) verbatim. A DockerSandbox (isolation
+// improvements, new safety checks) is explicitly out of scope for this phase.
+package sandbox
+
+import "context"
+
+// Sandbox is the environment a single task execution runs its tool calls
+// against.
+type Sandbox interface {
+	ReadFile(ctx context.Context, path string) (string, error)
+	WriteFile(ctx context.Context, path, content string) error
+	RunBash(ctx context.Context, command string) (stdout, stderr string, exitCode int, err error)
+	Glob(ctx context.Context, pattern string) ([]string, error)
+	GitClone(ctx context.Context, remote, branch string) error
+	GitPush(ctx context.Context, branch string) error
+	WorkDir() string
+	Cleanup(ctx context.Context) error
+}