Merge pull request #74 from Vect0rM/feature/atomic-chat-integration

feat: add support for Atomic Chat provider
2026-04-02 20:13:37 +08:00
parent 5cd95f4bb1 7c09b1f01c
commit 6b7c0e5339
11 changed files with 552 additions and 11 deletions
--- a/README.md
+++ b/README.md
@@ -2,7 +2,7 @@

 Use Claude Code with **any LLM** — not just Claude.

-OpenClaude is a fork of the [Claude Code source leak](https://gitlawb.com/node/repos/z6MkgKkb/instructkr-claude-code) (exposed via npm source maps on March 31, 2026). We added an OpenAI-compatible provider shim so you can plug in GPT-4o, DeepSeek, Gemini, Llama, Mistral, or any model that speaks the OpenAI chat completions API. It now also supports the ChatGPT Codex backend for `codexplan` and `codexspark`.
+OpenClaude is a fork of the [Claude Code source leak](https://gitlawb.com/node/repos/z6MkgKkb/instructkr-claude-code) (exposed via npm source maps on March 31, 2026). We added an OpenAI-compatible provider shim so you can plug in GPT-4o, DeepSeek, Gemini, Llama, Mistral, or any model that speaks the OpenAI chat completions API. It now also supports the ChatGPT Codex backend for `codexplan` and `codexspark`, and local inference via [Atomic Chat](https://atomic.chat/) on Apple Silicon.

 All of Claude Code's tools work — bash, file read/write/edit, grep, glob, agents, tasks, MCP — just powered by whatever model you choose.

@@ -140,6 +140,23 @@ export OPENAI_MODEL=llama3.3:70b
 # no API key needed for local models
 ```

+### Atomic Chat (local, Apple Silicon)
+
+```bash
+export CLAUDE_CODE_USE_OPENAI=1
+export OPENAI_BASE_URL=http://127.0.0.1:1337/v1
+export OPENAI_MODEL=your-model-name
+# no API key needed for local models
+```
+
+Or use the profile launcher:
+
+```bash
+bun run dev:atomic-chat
+```
+
+Download Atomic Chat from [atomic.chat](https://atomic.chat/). The app must be running with a model loaded before launching.
+
 ### LM Studio (local)

 ```bash
@@ -191,7 +208,7 @@ export OPENAI_MODEL=gpt-4o
 | Variable | Required | Description |
 |----------|----------|-------------|
 | `CLAUDE_CODE_USE_OPENAI` | Yes | Set to `1` to enable the OpenAI provider |
-| `OPENAI_API_KEY` | Yes* | Your API key (*not needed for local models like Ollama) |
+| `OPENAI_API_KEY` | Yes* | Your API key (*not needed for local models like Ollama/Atomic Chat) |
 | `OPENAI_MODEL` | Yes | Model name (e.g. `gpt-4o`, `deepseek-chat`, `llama3.3:70b`) |
 | `OPENAI_BASE_URL` | No | API endpoint (defaults to `https://api.openai.com/v1`) |
 | `CODEX_API_KEY` | Codex only | Codex/ChatGPT access token override |
@@ -254,6 +271,9 @@ bun run profile:codex
 # openai bootstrap with explicit key
 bun run profile:init -- --provider openai --api-key sk-...

+# atomic-chat bootstrap (auto-detects running model)
+bun run profile:init -- --provider atomic-chat
+
 # ollama bootstrap with custom model
 bun run profile:init -- --provider ollama --model llama3.1:8b

@@ -274,6 +294,9 @@ bun run dev:openai

 # Ollama profile (defaults: localhost:11434, llama3.1:8b)
 bun run dev:ollama
+
+# Atomic Chat profile (Apple Silicon local LLMs at 127.0.0.1:1337)
+bun run dev:atomic-chat
 ```

 `profile:recommend` ranks installed Ollama models for `latency`, `balanced`, or `coding`, and `profile:auto` can persist the recommendation directly.
@@ -284,8 +307,9 @@ Goal-based Ollama selection only recommends among models that are already instal

 Use `profile:codex` or `--provider codex` when you want the ChatGPT Codex backend.

-`dev:openai`, `dev:ollama`, and `dev:codex` run `doctor:runtime` first and only launch the app if checks pass.
+`dev:openai`, `dev:ollama`, `dev:atomic-chat`, and `dev:codex` run `doctor:runtime` first and only launch the app if checks pass.
 For `dev:ollama`, make sure Ollama is running locally before launch.
+For `dev:atomic-chat`, make sure Atomic Chat is running with a model loaded.

 ---

--- a/atomic_chat_provider.py
+++ b/atomic_chat_provider.py
@@ -0,0 +1,146 @@
+"""
+atomic_chat_provider.py
+-----------------------
+Adds native Atomic Chat support to openclaude.
+Lets Claude Code route requests to any locally-running model via
+Atomic Chat (Apple Silicon only) at 127.0.0.1:1337.
+
+Atomic Chat exposes an OpenAI-compatible API, so messages are forwarded
+directly without translation.
+
+Usage (.env):
+    PREFERRED_PROVIDER=atomic-chat
+    ATOMIC_CHAT_BASE_URL=http://127.0.0.1:1337
+"""
+
+import httpx
+import json
+import logging
+import os
+from typing import AsyncIterator
+
+logger = logging.getLogger(__name__)
+ATOMIC_CHAT_BASE_URL = os.getenv("ATOMIC_CHAT_BASE_URL", "http://127.0.0.1:1337")
+
+
+def _api_url(path: str) -> str:
+    return f"{ATOMIC_CHAT_BASE_URL}/v1{path}"
+
+
+async def check_atomic_chat_running() -> bool:
+    try:
+        async with httpx.AsyncClient(timeout=3.0) as client:
+            resp = await client.get(_api_url("/models"))
+            return resp.status_code == 200
+    except Exception:
+        return False
+
+
+async def list_atomic_chat_models() -> list[str]:
+    try:
+        async with httpx.AsyncClient(timeout=5.0) as client:
+            resp = await client.get(_api_url("/models"))
+            resp.raise_for_status()
+            data = resp.json()
+            return [m["id"] for m in data.get("data", [])]
+    except Exception as e:
+        logger.warning(f"Could not list Atomic Chat models: {e}")
+        return []
+
+
+async def atomic_chat(
+    model: str,
+    messages: list[dict],
+    system: str | None = None,
+    max_tokens: int = 4096,
+    temperature: float = 1.0,
+) -> dict:
+    chat_messages = list(messages)
+    if system:
+        chat_messages.insert(0, {"role": "system", "content": system})
+
+    payload = {
+        "model": model,
+        "messages": chat_messages,
+        "max_tokens": max_tokens,
+        "temperature": temperature,
+        "stream": False,
+    }
+
+    async with httpx.AsyncClient(timeout=120.0) as client:
+        resp = await client.post(_api_url("/chat/completions"), json=payload)
+        resp.raise_for_status()
+        data = resp.json()
+
+    choice = data.get("choices", [{}])[0]
+    assistant_text = choice.get("message", {}).get("content", "")
+    usage = data.get("usage", {})
+
+    return {
+        "id": data.get("id", "msg_atomic_chat"),
+        "type": "message",
+        "role": "assistant",
+        "content": [{"type": "text", "text": assistant_text}],
+        "model": model,
+        "stop_reason": "end_turn",
+        "stop_sequence": None,
+        "usage": {
+            "input_tokens": usage.get("prompt_tokens", 0),
+            "output_tokens": usage.get("completion_tokens", 0),
+        },
+    }
+
+
+async def atomic_chat_stream(
+    model: str,
+    messages: list[dict],
+    system: str | None = None,
+    max_tokens: int = 4096,
+    temperature: float = 1.0,
+) -> AsyncIterator[str]:
+    chat_messages = list(messages)
+    if system:
+        chat_messages.insert(0, {"role": "system", "content": system})
+
+    payload = {
+        "model": model,
+        "messages": chat_messages,
+        "max_tokens": max_tokens,
+        "temperature": temperature,
+        "stream": True,
+    }
+
+    yield "event: message_start\n"
+    yield f'data: {json.dumps({"type": "message_start", "message": {"id": "msg_atomic_chat_stream", "type": "message", "role": "assistant", "content": [], "model": model, "stop_reason": None, "usage": {"input_tokens": 0, "output_tokens": 0}}})}\n\n'
+    yield "event: content_block_start\n"
+    yield f'data: {json.dumps({"type": "content_block_start", "index": 0, "content_block": {"type": "text", "text": ""}})}\n\n'
+
+    async with httpx.AsyncClient(timeout=120.0) as client:
+        async with client.stream("POST", _api_url("/chat/completions"), json=payload) as resp:
+            resp.raise_for_status()
+            async for line in resp.aiter_lines():
+                if not line or not line.startswith("data: "):
+                    continue
+                raw = line[len("data: "):]
+                if raw.strip() == "[DONE]":
+                    break
+                try:
+                    chunk = json.loads(raw)
+                    delta = chunk.get("choices", [{}])[0].get("delta", {})
+                    delta_text = delta.get("content", "")
+                    if delta_text:
+                        yield "event: content_block_delta\n"
+                        yield f'data: {json.dumps({"type": "content_block_delta", "index": 0, "delta": {"type": "text_delta", "text": delta_text}})}\n\n'
+
+                    finish_reason = chunk.get("choices", [{}])[0].get("finish_reason")
+                    if finish_reason:
+                        usage = chunk.get("usage", {})
+                        yield "event: content_block_stop\n"
+                        yield f'data: {json.dumps({"type": "content_block_stop", "index": 0})}\n\n'
+                        yield "event: message_delta\n"
+                        yield f'data: {json.dumps({"type": "message_delta", "delta": {"stop_reason": "end_turn", "stop_sequence": None}, "usage": {"output_tokens": usage.get("completion_tokens", 0)}})}\n\n'
+                        yield "event: message_stop\n"
+                        yield f'data: {json.dumps({"type": "message_stop"})}\n\n'
+                        break
+                except json.JSONDecodeError:
+                    continue
--- a/package.json
+++ b/package.json
@@ -21,6 +21,7 @@
    "dev:gemini": "bun run scripts/provider-launch.ts gemini",
    "dev:ollama": "bun run scripts/provider-launch.ts ollama",
    "dev:ollama:fast": "bun run scripts/provider-launch.ts ollama --fast --bare",
+    "dev:atomic-chat": "bun run scripts/provider-launch.ts atomic-chat",
    "profile:init": "bun run scripts/provider-bootstrap.ts",
    "profile:recommend": "bun run scripts/provider-recommend.ts",
    "profile:auto": "bun run scripts/provider-recommend.ts --apply",
--- a/scripts/provider-bootstrap.ts
+++ b/scripts/provider-bootstrap.ts
@@ -10,6 +10,7 @@ import {
  recommendOllamaModel,
 } from '../src/utils/providerRecommendation.ts'
 import {
+  buildAtomicChatProfileEnv,
  buildCodexProfileEnv,
  buildGeminiProfileEnv,
  buildOllamaProfileEnv,
@@ -20,8 +21,11 @@ import {
  type ProviderProfile,
 } from '../src/utils/providerProfile.ts'
 import {
+  getAtomicChatChatBaseUrl,
  getOllamaChatBaseUrl,
+  hasLocalAtomicChat,
  hasLocalOllama,
+  listAtomicChatModels,
  listOllamaModels,
 } from './provider-discovery.ts'

@@ -34,7 +38,7 @@ function parseArg(name: string): string | null {

 function parseProviderArg(): ProviderProfile | 'auto' {
  const p = parseArg('--provider')?.toLowerCase()
-  if (p === 'openai' || p === 'ollama' || p === 'codex' || p === 'gemini') return p
+  if (p === 'openai' || p === 'ollama' || p === 'codex' || p === 'gemini' || p === 'atomic-chat') return p
  return 'auto'
 }

@@ -102,6 +106,21 @@ async function main(): Promise<void> {
        getOllamaChatBaseUrl,
      },
    )
+  } else if (selected === 'atomic-chat') {
+    const model = argModel || (await listAtomicChatModels(argBaseUrl || undefined))[0]
+    if (!model) {
+      if (!(await hasLocalAtomicChat(argBaseUrl || undefined))) {
+        console.error('Atomic Chat is not running (could not connect to 127.0.0.1:1337).\n  Download from https://atomic.chat/ and launch the application.')
+      } else {
+        console.error('Atomic Chat is running but no model is loaded. Open Atomic Chat and download or start a model first.')
+      }
+      process.exit(1)
+    }
+
+    env = buildAtomicChatProfileEnv(model, {
+      baseUrl: argBaseUrl,
+      getAtomicChatChatBaseUrl,
+    })
  } else if (selected === 'codex') {
    const builtEnv = buildCodexProfileEnv({
      model: argModel,
--- a/scripts/provider-discovery.ts
+++ b/scripts/provider-discovery.ts
@@ -1,6 +1,7 @@
 import type { OllamaModelDescriptor } from '../src/utils/providerRecommendation.ts'

 export const DEFAULT_OLLAMA_BASE_URL = 'http://localhost:11434'
+export const DEFAULT_ATOMIC_CHAT_BASE_URL = 'http://127.0.0.1:1337'

 function withTimeoutSignal(timeoutMs: number): {
  signal: AbortSignal
@@ -93,6 +94,69 @@ export async function listOllamaModels(
  }
 }

+// ── Atomic Chat discovery (Apple Silicon local LLMs at 127.0.0.1:1337) ──────
+
+export function getAtomicChatApiBaseUrl(baseUrl?: string): string {
+  const parsed = new URL(
+    baseUrl || process.env.ATOMIC_CHAT_BASE_URL || DEFAULT_ATOMIC_CHAT_BASE_URL,
+  )
+  const pathname = trimTrailingSlash(parsed.pathname)
+  parsed.pathname = pathname.endsWith('/v1')
+    ? pathname.slice(0, -3) || '/'
+    : pathname || '/'
+  parsed.search = ''
+  parsed.hash = ''
+  return trimTrailingSlash(parsed.toString())
+}
+
+export function getAtomicChatChatBaseUrl(baseUrl?: string): string {
+  return `${getAtomicChatApiBaseUrl(baseUrl)}/v1`
+}
+
+export async function hasLocalAtomicChat(baseUrl?: string): Promise<boolean> {
+  const { signal, clear } = withTimeoutSignal(1200)
+  try {
+    const response = await fetch(`${getAtomicChatChatBaseUrl(baseUrl)}/models`, {
+      method: 'GET',
+      signal,
+    })
+    return response.ok
+  } catch {
+    return false
+  } finally {
+    clear()
+  }
+}
+
+export async function listAtomicChatModels(
+  baseUrl?: string,
+): Promise<string[]> {
+  const { signal, clear } = withTimeoutSignal(5000)
+  try {
+    const response = await fetch(`${getAtomicChatChatBaseUrl(baseUrl)}/models`, {
+      method: 'GET',
+      signal,
+    })
+    if (!response.ok) {
+      return []
+    }
+
+    const data = await response.json() as {
+      data?: Array<{ id?: string }>
+    }
+
+    return (data.data ?? [])
+      .filter(model => Boolean(model.id))
+      .map(model => model.id!)
+  } catch {
+    return []
+  } finally {
+    clear()
+  }
+}
+
+// ── Ollama benchmarking ─────────────────────────────────────────────────────
+
 export async function benchmarkOllamaModel(
  modelName: string,
  baseUrl?: string,
--- a/scripts/provider-launch.ts
+++ b/scripts/provider-launch.ts
@@ -16,8 +16,11 @@ import {
  type ProviderProfile,
 } from '../src/utils/providerProfile.ts'
 import {
+  getAtomicChatChatBaseUrl,
  getOllamaChatBaseUrl,
+  hasLocalAtomicChat,
  hasLocalOllama,
+  listAtomicChatModels,
  listOllamaModels,
 } from './provider-discovery.ts'

@@ -48,7 +51,7 @@ function parseLaunchOptions(argv: string[]): LaunchOptions {
      continue
    }

-    if ((lower === 'auto' || lower === 'openai' || lower === 'ollama' || lower === 'codex' || lower === 'gemini') && requestedProfile === 'auto') {
+    if ((lower === 'auto' || lower === 'openai' || lower === 'ollama' || lower === 'codex' || lower === 'gemini' || lower === 'atomic-chat') && requestedProfile === 'auto') {
      requestedProfile = lower as ProviderProfile | 'auto'
      continue
    }
@@ -79,7 +82,7 @@ function loadPersistedProfile(): ProfileFile | null {
  if (!existsSync(path)) return null
  try {
    const parsed = JSON.parse(readFileSync(path, 'utf8')) as ProfileFile
-    if (parsed.profile === 'openai' || parsed.profile === 'ollama' || parsed.profile === 'codex' || parsed.profile === 'gemini') {
+    if (parsed.profile === 'openai' || parsed.profile === 'ollama' || parsed.profile === 'codex' || parsed.profile === 'gemini' || parsed.profile === 'atomic-chat') {
      return parsed
    }
    return null
@@ -96,6 +99,11 @@ async function resolveOllamaDefaultModel(
  return recommended?.name ?? null
 }

+async function resolveAtomicChatDefaultModel(): Promise<string | null> {
+  const models = await listAtomicChatModels()
+  return models[0] ?? null
+}
+
 function runCommand(command: string, env: NodeJS.ProcessEnv): Promise<number> {
  return runProcess(command, [], env)
 }
@@ -132,6 +140,10 @@ function printSummary(profile: ProviderProfile, env: NodeJS.ProcessEnv): void {
    console.log(`OPENAI_BASE_URL=${env.OPENAI_BASE_URL}`)
    console.log(`OPENAI_MODEL=${env.OPENAI_MODEL}`)
    console.log(`CODEX_API_KEY_SET=${Boolean(resolveCodexApiCredentials(env).apiKey)}`)
+  } else if (profile === 'atomic-chat') {
+    console.log(`OPENAI_BASE_URL=${env.OPENAI_BASE_URL}`)
+    console.log(`OPENAI_MODEL=${env.OPENAI_MODEL}`)
+    console.log('OPENAI_API_KEY_SET=false (local provider, no key required)')
  } else {
    console.log(`OPENAI_BASE_URL=${env.OPENAI_BASE_URL}`)
    console.log(`OPENAI_MODEL=${env.OPENAI_MODEL}`)
@@ -143,7 +155,7 @@ async function main(): Promise<void> {
  const options = parseLaunchOptions(process.argv.slice(2))
  const requestedProfile = options.requestedProfile
  if (!requestedProfile) {
-    console.error('Usage: bun run scripts/provider-launch.ts [openai|ollama|codex|gemini|auto] [--fast] [--goal <latency|balanced|coding>] [-- <cli args>]')
+    console.error('Usage: bun run scripts/provider-launch.ts [openai|ollama|codex|gemini|atomic-chat|auto] [--fast] [--goal <latency|balanced|coding>] [-- <cli args>]')
    process.exit(1)
  }

@@ -175,12 +187,30 @@ async function main(): Promise<void> {
    }
  }

+  let resolvedAtomicChatModel: string | null = null
+  if (
+    profile === 'atomic-chat' &&
+    (persisted?.profile !== 'atomic-chat' || !persisted?.env?.OPENAI_MODEL)
+  ) {
+    if (!(await hasLocalAtomicChat())) {
+      console.error('Atomic Chat is not running (could not connect to 127.0.0.1:1337).\n  Download from https://atomic.chat/ and launch the application.')
+      process.exit(1)
+    }
+    resolvedAtomicChatModel = await resolveAtomicChatDefaultModel()
+    if (!resolvedAtomicChatModel) {
+      console.error('Atomic Chat is running but no model is loaded. Open Atomic Chat and download or start a model first.')
+      process.exit(1)
+    }
+  }
+
  const env = await buildLaunchEnv({
    profile,
    persisted,
    goal: options.goal,
    getOllamaChatBaseUrl,
    resolveOllamaDefaultModel: async () => resolvedOllamaModel || 'llama3.1:8b',
+    getAtomicChatChatBaseUrl,
+    resolveAtomicChatDefaultModel: async () => resolvedAtomicChatModel,
  })
  if (options.fast) {
    applyFastFlags(env)
--- a/scripts/system-check.ts
+++ b/scripts/system-check.ts
@@ -186,7 +186,7 @@ function checkOpenAIEnv(): CheckResult[] {
  } else if (!key && !isLocalBaseUrl(request.baseUrl)) {
    results.push(fail('OPENAI_API_KEY', 'Missing key for non-local provider URL.'))
  } else if (!key) {
-    results.push(pass('OPENAI_API_KEY', 'Not set (allowed for local providers like Ollama/LM Studio).'))
+    results.push(pass('OPENAI_API_KEY', 'Not set (allowed for local providers like Atomic Chat/Ollama/LM Studio).'))
  } else {
    results.push(pass('OPENAI_API_KEY', 'Configured.'))
  }
@@ -271,6 +271,15 @@ async function checkBaseUrlReachability(): Promise<CheckResult> {
  }
 }

+function isAtomicChatUrl(baseUrl: string): boolean {
+  try {
+    const parsed = new URL(baseUrl)
+    return parsed.port === '1337' && isLocalBaseUrl(baseUrl)
+  } catch {
+    return false
+  }
+}
+
 function checkOllamaProcessorMode(): CheckResult {
  if (!isTruthy(process.env.CLAUDE_CODE_USE_OPENAI) || isTruthy(process.env.CLAUDE_CODE_USE_GEMINI)) {
    return pass('Ollama processor mode', 'Skipped (OpenAI-compatible mode disabled).')
@@ -281,6 +290,10 @@ function checkOllamaProcessorMode(): CheckResult {
    return pass('Ollama processor mode', 'Skipped (provider URL is not local).')
  }

+  if (isAtomicChatUrl(baseUrl)) {
+    return pass('Ollama processor mode', 'Skipped (Atomic Chat local provider detected, not Ollama).')
+  }
+
  const result = spawnSync('ollama', ['ps'], {
    cwd: process.cwd(),
    encoding: 'utf8',
--- a/smart_router.py
+++ b/smart_router.py
@@ -57,8 +57,8 @@ class Provider:
    @property
    def is_configured(self) -> bool:
        """True if the provider has an API key set."""
-        if self.name == "ollama":
-            return True  # Ollama needs no API key
+        if self.name in ("ollama", "atomic-chat"):
+            return True  # Local providers need no API key
        return bool(self.api_key)

    @property
@@ -93,6 +93,7 @@ def build_default_providers() -> list[Provider]:
    big = os.getenv("BIG_MODEL", "gpt-4.1")
    small = os.getenv("SMALL_MODEL", "gpt-4.1-mini")
    ollama_url = os.getenv("OLLAMA_BASE_URL", "http://localhost:11434")
+    atomic_chat_url = os.getenv("ATOMIC_CHAT_BASE_URL", "http://127.0.0.1:1337")

    return [
        Provider(
@@ -119,6 +120,14 @@ def build_default_providers() -> list[Provider]:
            big_model=big if "gemini" not in big and "gpt" not in big else "llama3:8b",
            small_model=small if "gemini" not in small and "gpt" not in small else "llama3:8b",
        ),
+        Provider(
+            name="atomic-chat",
+            ping_url=f"{atomic_chat_url}/v1/models",
+            api_key_env="",
+            cost_per_1k_tokens=0.0,   # free — local (Apple Silicon)
+            big_model=big if "gemini" not in big and "gpt" not in big else "llama3:8b",
+            small_model=small if "gemini" not in small and "gpt" not in small else "llama3:8b",
+        ),
    ]


--- a/src/utils/providerProfile.test.ts
+++ b/src/utils/providerProfile.test.ts
@@ -5,6 +5,7 @@ import { join } from 'node:path'
 import test from 'node:test'

 import {
+  buildAtomicChatProfileEnv,
  buildCodexProfileEnv,
  buildGeminiProfileEnv,
  buildLaunchEnv,
@@ -381,3 +382,72 @@ test('auto profile falls back to openai when no viable ollama model exists', ()
  assert.equal(selectAutoProfile(null), 'openai')
  assert.equal(selectAutoProfile('qwen2.5-coder:7b'), 'ollama')
 })
+
+// ── Atomic Chat profile tests ────────────────────────────────────────────────
+
+test('atomic-chat profiles never persist openai api keys', () => {
+  const env = buildAtomicChatProfileEnv('some-local-model', {
+    getAtomicChatChatBaseUrl: () => 'http://127.0.0.1:1337/v1',
+  })
+
+  assert.deepEqual(env, {
+    OPENAI_BASE_URL: 'http://127.0.0.1:1337/v1',
+    OPENAI_MODEL: 'some-local-model',
+  })
+  assert.equal('OPENAI_API_KEY' in env, false)
+})
+
+test('atomic-chat profiles respect custom base url', () => {
+  const env = buildAtomicChatProfileEnv('my-model', {
+    baseUrl: 'http://192.168.1.100:1337',
+    getAtomicChatChatBaseUrl: (baseUrl?: string) =>
+      baseUrl ? `${baseUrl}/v1` : 'http://127.0.0.1:1337/v1',
+  })
+
+  assert.equal(env.OPENAI_BASE_URL, 'http://192.168.1.100:1337/v1')
+  assert.equal(env.OPENAI_MODEL, 'my-model')
+})
+
+test('matching persisted atomic-chat env is reused for atomic-chat launch', async () => {
+  const env = await buildLaunchEnv({
+    profile: 'atomic-chat',
+    persisted: profile('atomic-chat', {
+      OPENAI_BASE_URL: 'http://127.0.0.1:1337/v1',
+      OPENAI_MODEL: 'llama-3.1-8b',
+    }),
+    goal: 'balanced',
+    processEnv: {},
+    getAtomicChatChatBaseUrl: () => 'http://127.0.0.1:1337/v1',
+    resolveAtomicChatDefaultModel: async () => 'other-model',
+  })
+
+  assert.equal(env.OPENAI_BASE_URL, 'http://127.0.0.1:1337/v1')
+  assert.equal(env.OPENAI_MODEL, 'llama-3.1-8b')
+  assert.equal(env.OPENAI_API_KEY, undefined)
+  assert.equal(env.CODEX_API_KEY, undefined)
+})
+
+test('atomic-chat launch ignores mismatched persisted openai env', async () => {
+  const env = await buildLaunchEnv({
+    profile: 'atomic-chat',
+    persisted: profile('openai', {
+      OPENAI_BASE_URL: 'https://api.openai.com/v1',
+      OPENAI_MODEL: 'gpt-4o',
+      OPENAI_API_KEY: 'sk-persisted',
+    }),
+    goal: 'balanced',
+    processEnv: {
+      OPENAI_API_KEY: 'sk-live',
+      CODEX_API_KEY: 'codex-live',
+      CHATGPT_ACCOUNT_ID: 'acct_live',
+    },
+    getAtomicChatChatBaseUrl: () => 'http://127.0.0.1:1337/v1',
+    resolveAtomicChatDefaultModel: async () => 'local-model',
+  })
+
+  assert.equal(env.OPENAI_BASE_URL, 'http://127.0.0.1:1337/v1')
+  assert.equal(env.OPENAI_MODEL, 'local-model')
+  assert.equal(env.OPENAI_API_KEY, undefined)
+  assert.equal(env.CODEX_API_KEY, undefined)
+  assert.equal(env.CHATGPT_ACCOUNT_ID, undefined)
+})
--- a/src/utils/providerProfile.ts
+++ b/src/utils/providerProfile.ts
@@ -13,7 +13,7 @@ import {
 const DEFAULT_GEMINI_BASE_URL = 'https://generativelanguage.googleapis.com/v1beta/openai'
 const DEFAULT_GEMINI_MODEL = 'gemini-2.0-flash'

-export type ProviderProfile = 'openai' | 'ollama' | 'codex' | 'gemini'
+export type ProviderProfile = 'openai' | 'ollama' | 'codex' | 'gemini' | 'atomic-chat'

 export type ProfileEnv = {
  OPENAI_BASE_URL?: string
@@ -53,6 +53,19 @@ export function buildOllamaProfileEnv(
  }
 }

+export function buildAtomicChatProfileEnv(
+  model: string,
+  options: {
+    baseUrl?: string | null
+    getAtomicChatChatBaseUrl: (baseUrl?: string) => string
+  },
+): ProfileEnv {
+  return {
+    OPENAI_BASE_URL: options.getAtomicChatChatBaseUrl(options.baseUrl ?? undefined),
+    OPENAI_MODEL: model,
+  }
+}
+
 export function buildGeminiProfileEnv(options: {
  model?: string | null
  baseUrl?: string | null
@@ -171,6 +184,8 @@ export async function buildLaunchEnv(options: {
  processEnv?: NodeJS.ProcessEnv
  getOllamaChatBaseUrl?: (baseUrl?: string) => string
  resolveOllamaDefaultModel?: (goal: RecommendationGoal) => Promise<string>
+  getAtomicChatChatBaseUrl?: (baseUrl?: string) => string
+  resolveAtomicChatDefaultModel?: () => Promise<string | null>
 }): Promise<NodeJS.ProcessEnv> {
  const processEnv = options.processEnv ?? process.env
  const persistedEnv =
@@ -248,6 +263,26 @@ export async function buildLaunchEnv(options: {
    return env
  }

+  if (options.profile === 'atomic-chat') {
+    const getAtomicChatBaseUrl =
+      options.getAtomicChatChatBaseUrl ?? (() => 'http://127.0.0.1:1337/v1')
+    const resolveModel =
+      options.resolveAtomicChatDefaultModel ?? (async () => null as string | null)
+
+    env.OPENAI_BASE_URL = persistedEnv.OPENAI_BASE_URL || getAtomicChatBaseUrl()
+    env.OPENAI_MODEL =
+      persistedEnv.OPENAI_MODEL ||
+      (await resolveModel()) ||
+      ''
+
+    delete env.OPENAI_API_KEY
+    delete env.CODEX_API_KEY
+    delete env.CHATGPT_ACCOUNT_ID
+    delete env.CODEX_ACCOUNT_ID
+
+    return env
+  }
+
  if (options.profile === 'codex') {
    env.OPENAI_BASE_URL =
      persistedEnv.OPENAI_BASE_URL && isCodexBaseUrl(persistedEnv.OPENAI_BASE_URL)
--- a/test_atomic_chat_provider.py
+++ b/test_atomic_chat_provider.py
@@ -0,0 +1,130 @@
+"""
+test_atomic_chat_provider.py
+Run: pytest test_atomic_chat_provider.py -v
+"""
+
+import pytest
+from unittest.mock import AsyncMock, MagicMock, patch
+from atomic_chat_provider import (
+    atomic_chat,
+    list_atomic_chat_models,
+    check_atomic_chat_running,
+)
+
+
+@pytest.mark.asyncio
+async def test_atomic_chat_running_true():
+    mock_response = MagicMock()
+    mock_response.status_code = 200
+    with patch("atomic_chat_provider.httpx.AsyncClient") as MockClient:
+        MockClient.return_value.__aenter__.return_value.get = AsyncMock(return_value=mock_response)
+        result = await check_atomic_chat_running()
+    assert result is True
+
+
+@pytest.mark.asyncio
+async def test_atomic_chat_running_false_on_exception():
+    with patch("atomic_chat_provider.httpx.AsyncClient") as MockClient:
+        MockClient.return_value.__aenter__.return_value.get = AsyncMock(side_effect=Exception("refused"))
+        result = await check_atomic_chat_running()
+    assert result is False
+
+
+@pytest.mark.asyncio
+async def test_list_models_returns_ids():
+    mock_response = MagicMock()
+    mock_response.status_code = 200
+    mock_response.json.return_value = {
+        "data": [{"id": "llama-3.1-8b"}, {"id": "mistral-7b"}],
+    }
+    mock_response.raise_for_status = MagicMock()
+    with patch("atomic_chat_provider.httpx.AsyncClient") as MockClient:
+        MockClient.return_value.__aenter__.return_value.get = AsyncMock(return_value=mock_response)
+        models = await list_atomic_chat_models()
+    assert "llama-3.1-8b" in models
+    assert "mistral-7b" in models
+
+
+@pytest.mark.asyncio
+async def test_list_models_empty_on_failure():
+    with patch("atomic_chat_provider.httpx.AsyncClient") as MockClient:
+        MockClient.return_value.__aenter__.return_value.get = AsyncMock(side_effect=Exception("down"))
+        models = await list_atomic_chat_models()
+    assert models == []
+
+
+@pytest.mark.asyncio
+async def test_atomic_chat_returns_anthropic_format():
+    mock_response = MagicMock()
+    mock_response.raise_for_status = MagicMock()
+    mock_response.json.return_value = {
+        "id": "chatcmpl-abc123",
+        "choices": [{"message": {"content": "42 is the answer."}}],
+        "usage": {"prompt_tokens": 10, "completion_tokens": 8},
+    }
+    with patch("atomic_chat_provider.httpx.AsyncClient") as MockClient:
+        MockClient.return_value.__aenter__.return_value.post = AsyncMock(return_value=mock_response)
+        result = await atomic_chat(
+            model="llama-3.1-8b",
+            messages=[{"role": "user", "content": "What is 6*7?"}],
+        )
+    assert result["type"] == "message"
+    assert result["role"] == "assistant"
+    assert "42" in result["content"][0]["text"]
+    assert result["usage"]["input_tokens"] == 10
+    assert result["usage"]["output_tokens"] == 8
+
+
+@pytest.mark.asyncio
+async def test_atomic_chat_prepends_system():
+    captured = {}
+
+    async def mock_post(url, json=None, **kwargs):
+        captured.update(json or {})
+        m = MagicMock()
+        m.raise_for_status = MagicMock()
+        m.json.return_value = {
+            "id": "chatcmpl-xyz",
+            "choices": [{"message": {"content": "ok"}}],
+            "usage": {"prompt_tokens": 1, "completion_tokens": 1},
+        }
+        return m
+
+    with patch("atomic_chat_provider.httpx.AsyncClient") as MockClient:
+        MockClient.return_value.__aenter__.return_value.post = mock_post
+        await atomic_chat(
+            model="llama-3.1-8b",
+            messages=[{"role": "user", "content": "Hi"}],
+            system="Be helpful.",
+        )
+    assert captured["messages"][0]["role"] == "system"
+    assert "helpful" in captured["messages"][0]["content"]
+
+
+@pytest.mark.asyncio
+async def test_atomic_chat_sends_correct_payload():
+    captured = {}
+
+    async def mock_post(url, json=None, **kwargs):
+        captured.update(json or {})
+        m = MagicMock()
+        m.raise_for_status = MagicMock()
+        m.json.return_value = {
+            "id": "chatcmpl-xyz",
+            "choices": [{"message": {"content": "ok"}}],
+            "usage": {"prompt_tokens": 1, "completion_tokens": 1},
+        }
+        return m
+
+    with patch("atomic_chat_provider.httpx.AsyncClient") as MockClient:
+        MockClient.return_value.__aenter__.return_value.post = mock_post
+        await atomic_chat(
+            model="test-model",
+            messages=[{"role": "user", "content": "Test"}],
+            max_tokens=2048,
+            temperature=0.5,
+        )
+    assert captured["model"] == "test-model"
+    assert captured["max_tokens"] == 2048
+    assert captured["temperature"] == 0.5
+    assert captured["stream"] is False