interactive-story/planning/reports/PHASE-0B-OFFLINE-NETWORK.md

Phase 0B — Offline and Network Behavior

Method: a Docker network created with --internal (no NAT, no DNS to the outside). The Ollama container was attached to it so the app could reach a model while having no path to the Internet. Isolation was verified from inside the app container before testing:

blocked ('1.1.1.1', 443)              OSError
blocked ('openrouter.ai', 443)        gaierror
blocked ('fonts.googleapis.com', 443) gaierror

AI-DnD — fails offline as shipped; fine once one file is vendored

First turn on the isolated network died. The SSE stream emitted the player event and stopped. Container log:

requests.exceptions.ConnectionError: HTTPSConnectionPool(
  host='openaipublic.blob.core.windows.net', port=443):
  Max retries exceeded with url: /encodings/cl100k_base.tiktoken
  (NameResolutionError ... Temporary failure in name resolution)

tiktoken downloads its BPE encoding on first use, and AI-DnD calls it for context budgeting on every turn. On the host this was invisible, because the file had already been cached to /tmp/data-gym-cache/9b5ad71b… during an earlier online run.

After copying that 1.7 MB file into the container:

OFFLINE TURN GENERATED: "I am Vale, an explorer. I journey alone through the
darkened depths of the lighthouse..."

So: a hard blocker on a clean air-gapped install, and a packaging fix — vendor the encoding (or pre-seed TIKTOKEN_CACHE_DIR, or replace the tokenizer). Worth stressing that static analysis could not have found this; it took an actually isolated run.

Other AI-DnD network surface:

• Google Fonts at runtime. The built SPA's index.html still contains fonts.googleapis.com/css2?family=Cinzel...&family=Crimson+Pro...&family=Inter..., and main.py's CSP explicitly allows fonts.googleapis.com / fonts.gstatic.com. Violates specification §12. Fix: self-host three families.
• Only other remote host in backend Python is https://openrouter.ai/api/v1, used as a default endpoint constant and a header-attribution host check. Both removable with the cloud-provider path.
• analytics.py is a self-hosted counter writing to two local tables. No third-party script, no outbound request. It records no IP, no user agent, and hashes the user id with HMAC. Removable, and not a telemetry leak in the meantime.
• Connection test and turns honour the configured endpoint only; no automatic URL retrieval or content fetching was observed.

Open Dungeon — runtime clean, build and telemetry are not

• Next.js telemetry is on by default and printed its notice on first start. Needs NEXT_TELEMETRY_DISABLED=1 or next telemetry disable in the production configuration.
• Fonts are fine at runtime. layout.tsx uses next/font/google, which downloads at build time and self-hosts. The served page contains no fonts.googleapis.com reference. The trade-off is that the build needs network access.
• Remote hosts referenced in src/: openrouter.ai (preset provider URL and a model list), plus ko-fi.com and github.com/sponsors donation links in the UI. Everything else is 127.0.0.1 / localhost (13 occurrences).
• Local story play needs no cloud service: Ollama for text, a local FLUX worker or the user's own ComfyUI for images.
• 335 npm packages with 6 high-severity advisories is the largest supply-chain surface of the three.

ai-adventure — verifiably local-only

The strongest posture by a wide margin, and the easiest to audit:

• Exactly one outbound call site in the whole codebase: urlopen in llm/lm_studio.py. Nothing else in local_adventure/ opens a socket.
• No hardcoded remote host anywhere. The only http string in the package is the scheme check in content/models.py.
• One direct dependency (pydantic), six packages in the closure.
• It is the only candidate that already implements specification §12's non-local-endpoint warning:

def _endpoint_warnings(config):
    hostname = urlparse(config.model.base_url).hostname
    if hostname not in {"127.0.0.1", "localhost", "::1"}:
        return ["model.base_url is not loopback; game prompts and content will
                 be sent to that endpoint. Enable API authentication."]

• audit.store_prompts defaults to false, with prompt hashes stored instead.
• Tests, world validation, session creation, replay, branching and export are all offline by construction.

Summary

	Local play works offline	Cloud service required	Telemetry / remote assets	Removal difficulty
AI-DnD	Only after vendoring the tiktoken encoding	No	Google Fonts at runtime; local-only analytics tables	Low — one vendored file, three self-hosted fonts, delete analytics
Open Dungeon	Yes at runtime; build needs network	No	Next.js telemetry on by default	Low — one env var; fonts already self-hosted
ai-adventure	Yes, unconditionally	No	None	Nothing to remove