diff --git a/.env.example b/.env.example
index 3878cd3..72c07d4 100644
--- a/.env.example
+++ b/.env.example
@@ -9,6 +9,8 @@ TEMPORAL_TASK_QUEUE=engineering
 # Claude worker (API mode). CLI mode (`claude -p`) uses the CLI's own login instead.
 ANTHROPIC_API_KEY=sk-ant-...
 # WORKER_MODE=api   # or "cli"
+# Model for agent runs (default claude-opus-4-8). Use claude-haiku-4-5 to run ~5x cheaper.
+# ANTHROPIC_MODEL=claude-opus-4-8
 
 # Delivery backend (ENG-017): "local" commits the agent's code to a local git repo under ./workspace
 # (no GitHub needed — QA verifies real code, tickets can reach `done` offline). Leave unset to use the
diff --git a/docker-compose.yml b/docker-compose.yml
index 1c23ec4..0652be5 100644
--- a/docker-compose.yml
+++ b/docker-compose.yml
@@ -96,6 +96,7 @@ services:
       TEMPORAL_ADDRESS: temporal:7233
       TEMPORAL_TASK_QUEUE: engineering
       ANTHROPIC_API_KEY: ${ANTHROPIC_API_KEY:-}
+      ANTHROPIC_MODEL: ${ANTHROPIC_MODEL:-}
       GITHUB_TOKEN: ${GITHUB_TOKEN:-}
       GITHUB_OWNER: ${GITHUB_OWNER:-}
       GITHUB_REPO: ${GITHUB_REPO:-}