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feat(claude): claude-vllm — run Claude Code against the homelab LLM gateway The gateway at llm.ad.itaz.eu is LiteLLM in front of vLLM, and LiteLLM already serves the Anthropic Messages API on /v1/messages — verified with a real completion. So Claude Code needs no bridge: pointing ANTHROPIC_BASE_URL at it is the whole integration. `claude-vllm` exists only to stop you pasting four exports each time. It reuses what another agent is already configured with — ~/.pi/agent, ~/.prime/agent, then opencode's config, first hit wins — taking the base URL and the credential from the same source so one gateway's URL is never paired with another's key. Beyond the obvious ANTHROPIC_* vars it sets two that are easy to miss: - ANTHROPIC_SMALL_FAST_MODEL / ANTHROPIC_DEFAULT_HAIKU_MODEL, or the background and summarisation calls ask the gateway for a real Haiku it does not serve and every one 404s; - CLAUDE_CODE_MAX_CONTEXT_TOKENS from the provider's declared contextWindow, because Claude Code assumes 200k for models it has no table for — and deepseek-v4-* is 393k, so it would auto-compact at half capacity. On `claude-mcpctl`: mcpctl's LLM layer is a client, not a server. mcpd serves /api/v1/llms (management) and its adapters call out to providers for gating, prompt selection and agent chat; nothing serves /v1/messages. Routing Claude through mcpctl would mean adding an Anthropic-shaped passthrough that re-wraps LiteLLM — worth doing only if mcpctl in the LLM path buys something of its own (per-project gating of model calls, prompt audit, budgets), which is a mcpd endpoint rather than a wrapper script. Verified: `claude-vllm --model deepseek-v4-fast -- -p "..."` completes against deepseek on the homelab, with the unknown-model context warning gone. Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01BVwuCjuMoA13gmzYEfcrNP
2026-08-09 18:39:36 +01:00
# `claude-vllm` — Claude Code on the homelab LLM
## The short version
```bash
claude-vllm # default provider + model
claude-vllm --model deepseek-v4-max
claude-vllm --list # what would it use?
claude-vllm --print-env # the exports, without running claude
claude-vllm -- -p "summarise this repo" # anything after -- goes to claude
```
## Why no bridge is needed
The homelab gateway at `llm.ad.itaz.eu` is **LiteLLM in front of vLLM**, and
LiteLLM already serves the Anthropic Messages API:
```console
$ curl -s https://llm.ad.itaz.eu/v1/messages -X POST \
-H 'x-api-key: <key>' -H 'anthropic-version: 2023-06-01' \
-d '{"model":"deepseek-v4-fast","max_tokens":32,
"messages":[{"role":"user","content":"say only: ok"}]}'
{"type":"message","role":"assistant","model":"deepseek-v4-fast",
"content":[{"type":"text","text":"ok"}],"stop_reason":"end_turn", …}
```
That is the exact protocol Claude Code speaks. So pointing `ANTHROPIC_BASE_URL`
at the gateway is the whole integration — no translation layer, no proxy, no
mcpctl in the request path.
### Why not route it through mcpctl
mcpctl's LLM layer is a **client**, not a server: `mcpd` exposes
`/api/v1/llms` (management) and the adapters in
`src/mcpd/src/services/llm/adapters/` *call out* to Anthropic/OpenAI for gating,
prompt selection and agent chat. Nothing in mcpd or mcplocal serves
`/v1/messages`. A `claude-mcpctl` would therefore mean adding an
Anthropic-shaped passthrough to mcpd that re-wraps what LiteLLM already does —
new surface, new failure mode, no new capability.
It would only be worth it if you wanted mcpctl *in* the LLM path for its own
sake: per-project gating of model calls, audit of prompts, or budget
enforcement. Those are real features, but they are a passthrough endpoint in
mcpd, not a wrapper script.
## What it discovers, and from where
`claude-vllm` exists only so you don't paste four exports each time. It reuses
whatever you already configured for another agent — first hit wins:
| Order | Source | Supplies |
|-------|--------|----------|
| 1 | environment (`ANTHROPIC_BASE_URL`, `ANTHROPIC_AUTH_TOKEN`, `ANTHROPIC_MODEL`) | anything already set is respected |
| 2 | `--provider` / `--model` flags | provider, model |
| 3 | `~/.pi/agent` | `settings.json` → default provider/model · `models.json` → base URL, context window · `auth.json` → key |
| 4 | `~/.prime/agent` | same shape |
| 5 | `~/.config/opencode/opencode.jsonc` | `provider.<name>.options.{baseURL,apiKey}` |
The base URL and the credential always come from the *same* source, so one
gateway's URL is never paired with another's key.
## What it sets, and why each one
| Variable | Reason |
|----------|--------|
| `ANTHROPIC_BASE_URL` | The gateway. A stored OpenAI-style `…/v1` base has the suffix stripped — Claude Code appends `/v1/messages` itself, and `/v1/v1/messages` 404s. |
| `ANTHROPIC_AUTH_TOKEN` + `ANTHROPIC_API_KEY` | The gateway takes either; which one Claude Code sends has changed between releases. |
| `ANTHROPIC_MODEL` | The model to drive the session. |
| `ANTHROPIC_SMALL_FAST_MODEL`, `ANTHROPIC_DEFAULT_HAIKU_MODEL` | Background/summarisation calls otherwise ask for a real Haiku the gateway does not serve, and every one 404s. |
| `CLAUDE_CODE_MAX_CONTEXT_TOKENS` | Claude Code assumes 200k for models it has no table for. `deepseek-v4-*` is 393k, so without this it auto-compacts at half capacity. Taken from `contextWindow` in the provider config. |
| `CLAUDE_CODE_DISABLE_EXPERIMENTAL_BETAS` | Beta headers the gateway does not implement make it reject otherwise-fine requests. |
| `CLAUDE_CODE_DISABLE_NONESSENTIAL_TRAFFIC` | No telemetry about a non-Anthropic endpoint. |
## Expected noise
```
⚠ claude.ai connectors are disabled because ANTHROPIC_API_KEY or another auth
source is set and takes precedence over your claude.ai login
```
Unavoidable and harmless: it fires for *any* non-claude.ai auth, including
`ANTHROPIC_AUTH_TOKEN` alone (verified). It means your claude.ai org connectors
are not loaded for this session — which is the point of running against the
homelab.
## Verified
```console
$ claude-vllm --model deepseek-v4-fast -- -p "Reply with exactly: PARITY-OK"
claude-vllm: itaz · deepseek-v4-fast · https://llm.ad.itaz.eu
PARITY-OK
```