ZEN FreeTier Watchlist — weekly lane re-check (Tam, Pulse lane)

• date: 2026-10-20
• tags: costgov, free-tier, zen, opencode-go, model-lanes, cron
• status: live (weekly re-check)
• source links: https://opencode.ai/zen/go/v1/models · ~/.hermes/profiles/tam/config.yaml · ~/vault/pulse/tools/zen_freetier_watch.py
• kanban: t_2742ee74
• related: goose-capability-assessment · 2026-09-27-cron-sync-inventory-audit

What this is

Fleet cost discipline (CostGov) runs every lane on the free ZEN Go tier first. This note tracks the free/contributor model catalog at https://opencode.ai/zen/go/v1 and the health of the lanes pinned in tam's config.yaml, re-checked weekly by zen_freetier_watch.py (cron zen-freetier-watch = job ddcf91338465, Mondays 09:00 AEDT, no_agent; failure signal = regression-only — exit 2 fires the Telegram alert to Young's Mind only when a previously-UP lane goes down or the catalog is unreachable; steady-state dead lanes ride the weekly stdout heartbeat). Catalog checks use the key authed /models call; each lane gets a 1-token completion probe. Machine-readable latest state: zen-freetier-latest.json (same dir). Script lives at ~/vault/pulse/tools/ (synced copy in ~/.hermes/profiles/tam/scripts/ — edit the tools/ one and re-copy).

Operations findings — 2026-10-20 (first full check, curl-verified)

• Gateway change: chat completions now require x-opencode-session header — without it every model returns 400 MissingSessionID and cannot be routed. Raw python urllib also gets Cloudflare 1010 on the same host; use curl or a real TLS stack. Any lane caller that predates the header requirement is silently broken.
• Catalog: 37 models listed. Fleet-relevant free/contributor entries: beam-free, longcat-2.5-preview-free, minimax-m3.1-flash-free, muse-spark-1.2-contributor, muse-spark-1.3-contributor.
• Lane probes (tam config.yaml chain):
  • ✅ UP: glm-5.3-flash (default), cat-jam-free, longcat-2.5-preview-free, minimax-m3.1-flash-free, deepseek-v4.1-flash, beam-free (spare capacity lane)
  • ⚠️ cat-jam-free delisted from catalog but still serves — fine for a fallback, do not promote it to a load-bearing lane.
  • ⚠️ Dead lanes (catalog-listed but 400 ModelProtocolUnsupported on chat completions): all contributor models — muse-spark-1.2-contributor, muse-spark-1.3-contributor, gemini-4-argon-contributor — plus tam-chain lane muse-spark-1.3-contributor. A catalog listing is not proof of service.
• Reasoning-model trap: small max_tokens (≤32) on glm-5.3-flash, cat-jam-free, longcat-2.5-preview-free burns the entire budget in reasoning_content — content comes back null and the caller looks "down" when it isn't. Probe with ≥512 tokens or treat null-content/finish=length as UP.

Config gap — OpenRouter tail has no local key

tam's fallback chain hops to OpenRouter after the ZEN lanes (nvidia/nemotron-3-ultra-550b-a55b:free, google/gemma-4-26b-a4b-it:free, …), but OPENROUTER_API_KEY is absent from ~/.hermes/profiles/tam/.env — if the whole ZEN chain 401s/403s, the tail cannot authenticate. Not fixed here (key addition is CostGov/Young's call); flagged as the top resilience gap.

Re-check 2026-10-21 (Tue, manual mid-cycle fire — run 2)

• No drift. Catalog unchanged (37 ids, byte-identical list), lane results an exact match of the 10-20 baseline: 6/9 UP (glm-5.3-flash, cat-jam-free, longcat-2.5-preview-free, minimax-m3.1-flash-free, beam-free, deepseek-v4.1-flash), 3 steady-state PROTO-400 contributor lanes, cat-jam-free still delisted-but-serving. x-opencode-session header still required (probes without it were not retried, but catalog 200s used it throughout). Productions regressions = — no alert fired, correct behaviour.
• Ops gap found + fixed: the LAB sync (sync_pulse_lab.sh) walks *.md only, so this note's siblings (zen-freetier-latest.json, zen_freetier_watch.py) never reach LAB via the 30m lane — the 10-20 "sha-verified on LAB" claim covered only the .md. Both non-md artifacts manually pushed via lab_ctrl_key shell lane on 10-21 and sha-verified laptop==LAB. Standing caveat: after any edit to the JSON/script, push them manually or they exist laptop-side only.

Weekly re-check log