Add model layer: async ModelAdapter (openai_compatible + mock) returning structured ModelOutput(text,tool_calls,usage), Deployer registry (vllm/sglang docker-pinned via models.yaml, external), async run_eval generate->score, CLI --model, agent-ready SampleResult.trajectory/env_state, tests

README.md

@@ -1,9 +1,10 @@
 # EvalHarness
 
-A plugin-based LLM/agent evaluation harness. **Currently: the data layer +
-the evaluation layer** (datasets & eval recipes as plugins, lazy
-materialization cache, official-aligned scorers, report artifacts & console
-visualization). Sandbox/model/tool/skill layers land one at a time.
+A plugin-based LLM/agent evaluation harness. **Currently: data + evaluation +
+model layers** (datasets/eval-recipes/model-adapters/deployers as plugins,
+lazy materialization cache, official-aligned scorers, async generation,
+report artifacts & console visualization). Sandbox/agent/tool/skill layers
+land one at a time.
 
 ## Features
 
@@ -147,6 +148,36 @@ Per-sample results keep `raw_prediction` + extraction note + score details;
 and re-running `evaluate()` re-scores the same predictions — the model is
 never re-queried.
 
+## Model layer (calling + deploying, separate plugins on purpose)
+
+```bash
+# generate + score in one command (async, concurrent)
+evalharness eval run gsm8k --model mock:boxed --limit 100          # offline pipeline check
+evalharness eval run gsm8k --model openai/http://gpu03:8000/v1?qwen3-8b
+evalharness eval run hle   --model openai/...?qwen3-8b --judge openai/...?gpt-4o
+# future: --model deploy:vllm/qwen3-8b  (Deployer pulls a pinned docker env)
+```
+
+Model spec grammar (plain strings):
+
+| spec | meaning |
+|---|---|
+| `mock` / `mock:boxed` / `mock:tool` | offline adapter (echo / oracle-boxed / tool-call) |
+| `openai/<api_base>?<model_id>` | any OpenAI-protocol endpoint: vllm, sglang, lmdeploy, ollama, cloud APIs |
+| `deploy:<engine>/<model>` | Deployer resolves the endpoint first (vllm/sglang: pinned docker image; external: models.yaml) |
+
+Design:
+
+- **ModelAdapter = how to call** (protocol). All adapters are `async` and
+  return structured `ModelOutput(text, tool_calls, usage)` — the hinge the
+  future agent loops hang on; single-turn recipes just read `.text`.
+- **Deployer = how to run** (environment, separate lifecycle). Docker images
+  are pinned per model in `models.yaml`, so `vllm:v0.9.2` and `vllm:v0.6.6`
+  stacks coexist on one machine; `external` connects to existing endpoints.
+- **Async boundary = waiting on the model**: `run_eval()` fans out calls with
+  a semaphore (default 32), collects raws + per-sample usage, then hands them
+  to the synchronous `evaluate()`. Data/scoring stay sync (fast, CPU/disk).
+
 ## Built-in datasets (28, official sources)
 
 | Family | Datasets (source) |
@@ -257,6 +288,11 @@ EvalHarness/
 │   │   ├── loader.py              # raw loading (local/HF/ModelScope native)
 │   │   ├── dataset.py             # Dataset: lazy materialize + cache + derived views
 │   │   └── datasets/              # 28 built-in single-file dataset plugins
+│   ├── model/                     # ---- model layer ----
+│   │   ├── output.py              # ModelOutput/ToolCall/Usage (agent hinge)
+│   │   ├── adapter.py             # @register_adapter: openai_compatible / mock
+│   │   ├── deployer.py            # @register_deployer: vllm / sglang / external
+│   │   └── runner.py              # async run_eval(): generate -> evaluate
 │   ├── eval/                      # ---- evaluation layer ----
 │   │   ├── record.py              # SampleResult / EvalReport artifacts
 │   │   ├── extractor.py           # answer-extraction primitives (+cascades)
@@ -279,7 +315,11 @@ EvalHarness/
 - [x] Data layer (28 dataset plugins, lazy cache, native HF/ModelScope loaders)
 - [x] Evaluation layer (extract/score/aggregate plugins, official scorers, recipes)
 - [x] Visualization (console/markdown renderers over report artifacts)
-- [ ] Model layer (ModelAdapter: unified URL-based invocation; wires llm_judge)
+- [x] Model layer (async ModelAdapter openai_compatible+mock, ModelOutput
+      with tool_calls, Deployer registry vllm/sglang/external + models.yaml
+      env pinning, run_eval generate->score)
+- [ ] Agent layer (loops: single_turn fast path today, react/plan_execute;
+      environments: tau2 user-sim, swe docker; SampleResult.trajectory ready)
 - [ ] Sandbox layer (materialize `Sample.sandbox`: lazy per-instance image
       pull, refcounted image unload, container lifecycle; `requires` gating)
 - [ ] Tool layer (data filter/synthesis/dedup/export; Dataset in, Dataset out)

evalharness/cli.py

@@ -108,18 +108,27 @@ def _cmd_eval_list(_args) -> int:
 
 
 def _cmd_eval_run(args) -> int:
-    from evalharness.eval import evaluate, get_eval
+    import asyncio
+
     from evalharness.data import get_dataset
+    from evalharness.viz import render
 
     ds = get_dataset(args.dataset, **_overrides(args))
+    if args.model:  # generate + score in one go
+        from evalharness.model import run_eval
+
+        report = asyncio.run(run_eval(
+            ds, args.model, concurrency=args.concurrency, limit=args.limit,
+            judge_spec=args.judge))
+    else:
+        from evalharness.eval import evaluate
+
         preds = [json.loads(line) for line in open(args.predictions, encoding='utf-8') if line.strip()]
         preds = [p.get('raw', p.get('prediction', '')) if isinstance(p, dict) else p for p in preds]
-    report = evaluate(ds, preds, model=args.model)
+        report = evaluate(ds, preds, model=args.model or 'preds')
     if args.out:
         report.save(args.out)
         print(f'saved -> {args.out}')
-    from evalharness.viz import render
-
     print(render(report, style=args.style))
     return 0
 
@@ -171,10 +180,15 @@ def build_parser() -> argparse.ArgumentParser:
     p = esub.add_parser('list', help='list registered eval recipes')
     p.set_defaults(func=_cmd_eval_list)
 
-    p = esub.add_parser('run', help='score predictions against a dataset')
+    p = esub.add_parser('run', help='score predictions (file) or generate+score (--model)')
     p.add_argument('dataset', help='dataset name (recipe auto-resolved)')
-    p.add_argument('predictions', help='jsonl: one raw string or {"raw": ...} per sample')
-    p.add_argument('--model', default='', help='model tag recorded in the report')
+    p.add_argument('predictions', nargs='?', help='jsonl: one raw string or {"raw": ...} per sample')
+    p.add_argument('--model', default='',
+                   help="generate with model spec: mock | mock:boxed | "
+                        "openai/http://host:8000/v1?model | deploy:vllm/model")
+    p.add_argument('--judge', default='', help='judge model spec for llm_judge recipes')
+    p.add_argument('--concurrency', type=int, default=32, help='parallel model calls (default 32)')
+    p.add_argument('--limit', type=int, help='evaluate only the first N samples')
     p.add_argument('--out', help='save the EvalReport json here')
     p.add_argument('--style', default='text', help='result render style (text/md/radar/errors)')
     _add_override_flags(p)

evalharness/eval/record.py

@@ -36,6 +36,13 @@ class SampleResult(BaseModel):
     metadata: Dict[str, Any] = Field(default_factory=dict)
     error: str = ''                           # scorer/extractor exception (never silently dropped)
 
+    # agent hinge: when a future AgentLoop produces multi-turn trajectories,
+    # they land here (list of ChatMessage dumps) + final environment state;
+    # env_reward scorers consume these instead of extracted text
+    trajectory: Optional[List[Dict[str, Any]]] = None
+    env_state: Optional[Dict[str, Any]] = None
+    usage: Optional[Dict[str, Any]] = None    # tokens/cost/latency per sample
+
 
 class EvalReport(BaseModel):
     """Aggregated artifact: what a viewer/visualizer consumes."""

evalharness/eval/runner.py

@@ -69,6 +69,12 @@ def evaluate(
         )
         if isinstance(pred, dict) and pred.get('metadata'):
             result.metadata.update(pred['metadata'])
+        if isinstance(pred, dict) and pred.get('trajectory'):
+            result.trajectory = pred['trajectory']
+        if isinstance(pred, dict) and pred.get('env_state'):
+            result.env_state = pred['env_state']
+        if isinstance(pred, dict) and pred.get('usage'):
+            result.usage = pred['usage']
         try:
             value, ok, note = extractor(raw, sample)
             result.extracted_prediction = value

evalharness/model/__init__.py

@@ -0,0 +1,45 @@
+"""evalharness.model -- calling and deploying models.
+
+Two plugin families, deliberately separate lifecycles:
+  ModelAdapter  HOW to call (protocol): openai_compatible, mock, ...
+  Deployer      HOW to run  (environment): vllm, sglang, external (docker-pinned)
+
+Model spec grammar (strings everywhere, no config ceremony):
+  mock / mock:boxed / mock:tool          offline
+  openai/http://host:8000/v1?model_id    any OpenAI-protocol endpoint (vllm, sglang, cloud)
+  deploy:vllm/qwen3-8b                   Deployer resolves endpoint (models.yaml pins env)
+
+All adapters are async and return structured ModelOutput(text, tool_calls,
+usage) -- the hinge the future agent loops hang on.
+"""
+
+from .adapter import (
+    ADAPTER_REGISTRY,
+    ModelAdapter,
+    OpenAICompatible,
+    MockAdapter,
+    register_adapter,
+    resolve_adapter,
+    parse_model_spec,
+)
+from .deployer import (
+    DEPLOYER_REGISTRY,
+    Deployer,
+    VLLMDeployer,
+    SGLangDeployer,
+    External,
+    deploy,
+    load_model_config,
+    register_deployer,
+    stop_all,
+)
+from .output import ModelOutput, ToolCall, Usage
+from .runner import generate_predictions, run_eval
+
+__all__ = [
+    'ModelAdapter', 'OpenAICompatible', 'MockAdapter', 'register_adapter',
+    'resolve_adapter', 'parse_model_spec', 'ADAPTER_REGISTRY',
+    'Deployer', 'VLLMDeployer', 'SGLangDeployer', 'External',
+    'register_deployer', 'deploy', 'stop_all', 'load_model_config', 'DEPLOYER_REGISTRY',
+    'ModelOutput', 'ToolCall', 'Usage', 'generate_predictions', 'run_eval',
+]

evalharness/model/adapter.py

@@ -0,0 +1,227 @@
+"""ModelAdapter: HOW to call a model (protocol level). Never deploys anything.
+
+Registry + two built-ins:
+  openai_compatible   -- /v1/chat/completions; covers vllm, sglang, lmdeploy,
+                         ollama, tgi, and every OpenAI-protocol cloud API
+  mock                -- offline deterministic/testing adapter
+
+Model spec grammar (a single string, no config files needed for the common case):
+  openai/http://localhost:8000/v1?qwen3-8b        adapter + api_base + model id
+  openai/https://api.openai.com/v1?gpt-4o         (OPENAI_API_KEY read from env)
+  anthropic/claude-...                            (provider-native protocols later)
+  mock                                            offline
+  deploy:vllm/qwen3-8b                            -> Deployer resolves to an endpoint,
+                                                    then re-dispatches as openai/...
+"""
+
+import json
+import os
+import re
+from typing import Any, Dict, List, Optional
+
+from ..data.sample import ChatMessage
+from ..eval.registry import EvalRegistry
+from .output import ModelOutput, ToolCall, Usage
+
+ADAPTER_REGISTRY = EvalRegistry('model adapter')
+
+
+def register_adapter(name: str):
+    def decorator(cls):
+        ADAPTER_REGISTRY.register(name, cls)
+        return cls
+
+    return decorator
+
+
+class ModelAdapter:
+    """Base class. Subclasses implement generate() (async, structured output)."""
+
+    name = 'base'
+
+    def __init__(self, model: str = '', api_base: str = '', api_key: str = '', **kwargs):
+        self.model = model
+        self.api_base = api_base.rstrip('/')
+        self.api_key = api_key
+        self.extra = kwargs
+
+    async def generate(
+        self,
+        messages: List[ChatMessage],
+        tools: Optional[List[Dict[str, Any]]] = None,
+        **gen_kwargs,
+    ) -> ModelOutput:
+        raise NotImplementedError
+
+    async def close(self) -> None:
+        pass
+
+    def __repr__(self):
+        return f'{type(self).__name__}(model={self.model!r}, base={self.api_base!r})'
+
+
+# --------------------------- spec parsing / dispatch ---------------------------
+
+_SPEC_RE = re.compile(r'^(?P<adapter>[a-z_]+)(/(?P<rest>.+))?$')
+_DEPLOY_RE = re.compile(r'^deploy:(?P<deployer>[a-z0-9_-]+)/(?P<model>.+)$')
+
+
+def parse_model_spec(spec: str) -> Dict[str, str]:
+    """'openai/http://x:8000/v1?qwen' -> {adapter, api_base, model}."""
+    m = _SPEC_RE.match(spec.strip())
+    if not m:
+        raise ValueError(f'bad model spec: {spec!r} (expected adapter/rest?model)')
+    adapter = m.group('adapter')
+    rest = m.group('rest') or ''
+    api_base, _, model = rest.partition('?')
+    return {'adapter': adapter, 'api_base': api_base, 'model': model}
+
+
+def resolve_adapter(spec: str, deploy_fn=None) -> ModelAdapter:
+    """Spec -> adapter instance. deploy:... specs go through a Deployer first."""
+    m = _DEPLOY_RE.match(spec.strip())
+    if m:
+        if deploy_fn is None:
+            from .deployer import deploy as default_deploy
+            deploy_fn = default_deploy
+        endpoint = deploy_fn(m.group('deployer'), m.group('model'))
+        spec = f"openai/{endpoint['api_base']}?{endpoint['model']}"
+    parsed = parse_model_spec(spec)
+    cls = ADAPTER_REGISTRY.get(parsed['adapter'])
+    key = parsed.get('api_base') and _key_for(parsed['api_base'])
+    return cls(model=parsed['model'], api_base=parsed['api_base'], api_key=key)
+
+
+def _key_for(api_base: str) -> str:
+    """Best-effort API key by endpoint; explicit env always wins."""
+    for host_hint, var in (('api.openai.com', 'OPENAI_API_KEY'),
+                           ('anthropic.com', 'ANTHROPIC_API_KEY'),
+                           ('dashscope', 'DASHSCOPE_API_KEY'),
+                           ('bigmodel', 'ZAI_API_KEY')):
+        if host_hint in api_base:
+            return os.environ.get(var, '')
+    return os.environ.get('OPENAI_API_KEY', '')
+
+
+# --------------------------- openai_compatible ---------------------------
+
+
+@register_adapter('openai')
+class OpenAICompatible(ModelAdapter):
+    """Async OpenAI chat-completions client with zero hard dependencies.
+
+    Uses httpx if installed (proper async); falls back to urllib in a thread
+    so the core install stays dependency-free.
+    """
+
+    name = 'openai'
+
+    async def generate(self, messages, tools=None, **kw) -> ModelOutput:
+        payload = self._payload(messages, tools, kw)
+        headers = {'Content-Type': 'application/json'}
+        if self.api_key:
+            headers['Authorization'] = f'Bearer {self.api_key}'
+        data = await self._post(f'{self.api_base}/chat/completions', payload, headers)
+        return self._parse(data)
+
+    def _payload(self, messages, tools, kw) -> Dict[str, Any]:
+        msgs = [{'role': m.role, 'content': m.content} for m in messages]
+        payload: Dict[str, Any] = {'model': self.model, 'messages': msgs}
+        if tools:
+            payload['tools'] = [
+                {'type': 'function', 'function': t} if 'function' not in t else t for t in tools
+            ]
+        for k in ('temperature', 'max_tokens', 'top_p', 'stop', 'seed', 'response_format'):
+            if kw.get(k) is not None:
+                payload[k] = kw[k]
+        return payload
+
+    def _parse(self, data: Dict[str, Any]) -> ModelOutput:
+        choice = (data.get('choices') or [{}])[0]
+        msg = choice.get('message') or {}
+        calls = []
+        for c in msg.get('tool_calls') or []:
+            fn = c.get('function') or {}
+            args = fn.get('arguments') or '{}'
+            try:
+                args_dict = json.loads(args)
+            except (ValueError, TypeError):
+                args_dict = {}
+            calls.append(ToolCall(id=c.get('id', ''), name=fn.get('name', ''),
+                                  arguments=args, arguments_dict=args_dict))
+        u = data.get('usage') or {}
+        usage = Usage(input_tokens=u.get('prompt_tokens', 0),
+                      output_tokens=u.get('completion_tokens', 0),
+                      total_tokens=u.get('total_tokens', 0),
+                      finish_reason=choice.get('finish_reason', ''))
+        return ModelOutput(text=msg.get('content') or '', tool_calls=calls, usage=usage,
+                           raw=data, model=data.get('model', self.model))
+
+    async def _post(self, url: str, payload: Dict, headers: Dict) -> Dict[str, Any]:
+        try:
+            import httpx
+
+            async with httpx.AsyncClient(timeout=self.extra.get('timeout', 600)) as client:
+                r = await client.post(url, json=payload, headers=headers)
+                r.raise_for_status()
+                return r.json()
+        except ImportError:
+            import asyncio
+            import urllib.request
+
+            def _sync():
+                req = urllib.request.Request(url, data=json.dumps(payload).encode(),
+                                             headers=headers, method='POST')
+                with urllib.request.urlopen(req, timeout=self.extra.get('timeout', 600)) as resp:
+                    return json.loads(resp.read().decode())
+
+            return await asyncio.to_thread(_sync)
+
+
+# --------------------------- mock ---------------------------
+
+_MOCK_PATTERNS = (
+    (re.compile(r'\\boxed\{([^}]*)\}'), None),   # echo any boxed target in the input
+)
+
+
+@register_adapter('mock')
+class MockAdapter(ModelAdapter):
+    """Offline adapter for tests/CI/dev.
+
+    Modes (extra['mode']):
+      echo      -- return the input text (default)
+      boxed     -- return \\boxed{<target>} scraped from the last user message
+                   (metadata['mock_target'] or first number found)
+      tool      -- return one tool call named extra['tool_name']
+      const     -- return extra['text']
+    """
+
+    name = 'mock'
+
+    async def generate(self, messages, tools=None, **kw) -> ModelOutput:
+        mode = self.extra.get('mode', 'echo')
+        if mode == 'const':
+            text = self.extra.get('text', 'mock')
+        elif mode == 'tool':
+            name = self.extra.get('tool_name', 'dummy_tool')
+            return ModelOutput(text='', tool_calls=[ToolCall(
+                name=name, arguments='{}', arguments_dict={})], model='mock')
+        else:
+            last = next((m.content for m in reversed(messages) if m.role == 'user'), '')
+            text = last
+            if mode == 'boxed':
+                # cheat-mode for pipeline verification: an oracle message
+                # (metadata-free) can't know the target, so the runner tags
+                # the message with 'mock_target' when samples carry one
+                target = None
+                for m in reversed(messages):
+                    if m.role == 'user' and m.content.startswith('MOCKTARGET::'):
+                        target = m.content[len('MOCKTARGET::'):]
+                        break
+                if target is None:
+                    m = _MOCK_PATTERNS[0][0].search(last)
+                    target = m.group(1) if m else (re.findall(r'-?\d+\.?\d*', last) or ['0'])[-1]
+                text = f'The answer is \\boxed{{{target}}}.'
+        return ModelOutput(text=text, model='mock', usage=Usage(
+            input_tokens=1, output_tokens=1, total_tokens=2, finish_reason='stop'))

evalharness/model/deployer.py

@@ -0,0 +1,187 @@
+"""Deployer: HOW to run a model (environment level). Never scores anything.
+
+Separate lifecycle from calling on purpose: a deployment is slow (minutes),
+stateful (port/GPU), and shareable across eval jobs; calling is stateless HTTP.
+
+Built-ins:
+  vllm       -- docker run vllm/vllm-openji:<tag> (image pin = environment pin;
+                override per-model via models.yaml so multiple versions coexist)
+  sglang     -- docker run lmsysorg/sglang:<tag>
+  external   -- nothing to do; endpoint already exists (default for cloud APIs)
+
+Environment binding is DECLARATIVE (models.yaml), never code:
+
+    models:
+      qwen3-8b:
+        deployer: vllm
+        image: vllm/vllm-openai:v0.9.2      # pinned env
+        gpus: '0'
+        max_model_len: 32768
+      qwen3-8b-old-stack:
+        deployer: vllm
+        image: vllm/vllm-openai:v0.6.6.post1   # same model, different env, coexists
+        port: 8001
+
+resolve('vllm', 'qwen3-8b') -> {'api_base': ..., 'model': ...}
+"""
+
+import os
+import shlex
+import subprocess
+import time
+from pathlib import Path
+from typing import Any, Dict, List, Optional
+
+from ..eval.registry import EvalRegistry
+
+DEPLOYER_REGISTRY = EvalRegistry('deployer')
+
+
+def register_deployer(name: str):
+    def decorator(cls):
+        DEPLOYER_REGISTRY.register(name, cls)
+        return cls
+
+    return decorator
+
+
+def _models_yaml_path() -> Path:
+    return Path(os.environ.get('EVALHARNESS_MODELS', 'models.yaml')).expanduser()
+
+
+_CONFIG: Optional[Dict[str, Dict[str, Any]]] = None
+
+
+def load_model_config() -> Dict[str, Dict[str, Any]]:
+    """models.yaml -> {model_name: {deployer, image, ...}} (cached; {} if absent)."""
+    global _CONFIG
+    if _CONFIG is None:
+        import yaml  # optional; falls back to {} without it
+
+        path = _models_yaml_path()
+        _CONFIG = {}
+        if path.exists():
+            with open(path, encoding='utf-8') as f:
+                _CONFIG = (yaml.safe_load(f) or {}).get('models', {}) or {}
+    return _CONFIG
+
+
+def _free_port() -> int:
+    import socket
+
+    with socket.socket() as s:
+        s.bind(('', 0))
+        return s.getsockname()[1]
+
+
+class Deployer:
+    """Base class: deploy(name, cfg) -> {'api_base', 'model'} (idempotent)."""
+
+    name = 'base'
+
+    def deploy(self, model: str, cfg: Dict[str, Any]) -> Dict[str, str]:
+        raise NotImplementedError
+
+    def stop(self, handle: Dict[str, Any]) -> None:
+        pass
+
+
+@register_deployer('external')
+class External(Deployer):
+    """Endpoint already exists; cfg: api_base, model, api_key."""
+
+    name = 'external'
+
+    def deploy(self, model: str, cfg: Dict[str, Any]) -> Dict[str, str]:
+        api_base = cfg.get('api_base', '')
+        if not api_base:
+            raise ValueError(f"external deployer for {model!r} needs api_base in models.yaml")
+        return {'api_base': api_base, 'model': cfg.get('model', model)}
+
+
+class DockerServeDeployer(Deployer):
+    """Shared docker-run logic for OpenAI-protocol serving engines."""
+
+    engine_args: List[str] = []
+
+    def deploy(self, model: str, cfg: Dict[str, Any]) -> Dict[str, str]:
+        image = cfg.get('image', self.default_image)
+        port = int(cfg.get('port', 0) or _free_port())
+        hf = cfg.get('hf_home', os.environ.get('HF_HOME', '~/.cache/huggingface'))
+        gpus = cfg.get('gpus', 'all')
+        cmd = [
+            'docker', 'run', '-d', '--rm',
+            '--name', f'evalharness-{self.name}-{model}-{port}'.replace('/', '-'),
+            '--gpus', f'device={gpus}' if str(gpus).isdigit() else str(gpus),
+            '-p', f'{port}:8000',
+            '-v', f'{Path(hf).expanduser()}:/root/.cache/huggingface',
+            '-e', f'HF_ENDPOINT={os.environ.get("HF_ENDPOINT", "https://hf-mirror.com")}',
+            image, '--model', cfg.get('model_id', cfg.get('model', model)),
+            '--served-model-name', model,
+            *self.engine_args,
+            *shlex.split(cfg.get('extra_args', '')),
+        ]
+        if cfg.get('gpu_mem_util'):
+            cmd += ['--gpu-memory-utilization', str(cfg['gpu_mem_util'])]
+        if cfg.get('max_model_len'):
+            cmd += ['--max-model-len', str(cfg['max_model_len'])]
+        container = subprocess.run(cmd, capture_output=True, text=True, check=True).stdout.strip()
+        api_base = f'http://localhost:{port}/v1'
+        self._wait_healthy(api_base, cfg.get('timeout_s', 1800))
+        return {'api_base': api_base, 'model': model, 'container': container}
+
+    def _wait_healthy(self, api_base: str, timeout_s: int) -> None:
+        deadline = time.time() + timeout_s
+        while time.time() < deadline:
+            try:
+                import urllib.request
+
+                req = urllib.request.Request(f'{api_base}/models')
+                with urllib.request.urlopen(req, timeout=5) as resp:
+                    if resp.status == 200:
+                        return
+            except Exception:
+                time.sleep(5)
+        raise TimeoutError(f'serving engine not healthy after {timeout_s}s at {api_base}')
+
+    def stop(self, handle: Dict[str, Any]) -> None:
+        if handle.get('container'):
+            subprocess.run(['docker', 'rm', '-f', handle['container']], check=False)
+
+
+@register_deployer('vllm')
+class VLLMDeployer(DockerServeDeployer):
+    name = 'vllm'
+    default_image = 'vllm/vllm-openai:v0.9.2'
+
+
+@register_deployer('sglang')
+class SGLangDeployer(DockerServeDeployer):
+    name = 'sglang'
+    default_image = 'lmsysorg/sglang:latest'
+
+
+_ACTIVE: Dict[str, Dict[str, str]] = {}
+
+
+def deploy(deployer: str, model: str) -> Dict[str, str]:
+    """Resolve deploy:<deployer>/<model> specs. Idempotent per (deployer, model)."""
+    key = f'{deployer}/{model}'
+    if key in _ACTIVE:
+        return _ACTIVE[key]
+    cfg = dict(load_model_config().get(model, {}))
+    cls = DEPLOYER_REGISTRY.get(deployer)
+    handle = cls().deploy(model, cfg)
+    _ACTIVE[key] = handle
+    return handle
+
+
+def stop_all() -> None:
+    """Stop everything this process started (atexit-registered by runner)."""
+    for key, handle in _ACTIVE.items():
+        cls = DEPLOYER_REGISTRY.get(key.split('/', 1)[0])
+        try:
+            cls().stop(handle)
+        except Exception:
+            pass
+    _ACTIVE.clear()

evalharness/model/output.py

@@ -0,0 +1,59 @@
+"""Structured model output -- the hinge between single-turn eval and agents.
+
+Every ModelAdapter returns ModelOutput, never a bare string:
+  - single-turn recipes read .text
+  - agent loops read .tool_calls and feed observations back
+  - accounting/monitoring reads .usage
+"""
+
+import time
+from typing import Any, Dict, List, Optional
+
+from pydantic import BaseModel, Field
+
+
+class ToolCall(BaseModel):
+    """One function call the model wants executed (OpenAI tool_calls shape)."""
+
+    id: str = ''
+    name: str
+    arguments: str = ''                 # JSON-encoded args string
+    arguments_dict: Dict[str, Any] = Field(default_factory=dict)  # parsed convenience
+
+    def to_openai(self) -> Dict[str, Any]:
+        return {'id': self.id or f'call_{self.name}', 'type': 'function',
+                'function': {'name': self.name, 'arguments': self.arguments or '{}'}}
+
+
+class Usage(BaseModel):
+    input_tokens: int = 0
+    output_tokens: int = 0
+    total_tokens: int = 0
+    cost: float = 0.0
+    latency_s: float = 0.0
+    finish_reason: str = ''
+
+    def __add__(self, other: 'Usage') -> 'Usage':
+        return Usage(
+            input_tokens=self.input_tokens + other.input_tokens,
+            output_tokens=self.output_tokens + other.output_tokens,
+            total_tokens=self.total_tokens + other.total_tokens,
+            cost=round(self.cost + other.cost, 6),
+            latency_s=round(self.latency_s + other.latency_s, 3),
+            finish_reason=self.finish_reason or other.finish_reason,
+        )
+
+
+class ModelOutput(BaseModel):
+    """What every adapter returns. text may be '' when the model only calls tools."""
+
+    text: str = ''
+    tool_calls: List[ToolCall] = Field(default_factory=list)
+    usage: Usage = Field(default_factory=Usage)
+    raw: Optional[Dict[str, Any]] = None    # provider response (audit/retry)
+    model: str = ''
+    created_at: str = Field(default_factory=lambda: time.strftime('%Y-%m-%d %H:%M:%S'))
+
+    @property
+    def is_tool_call(self) -> bool:
+        return bool(self.tool_calls)

evalharness/model/runner.py

@@ -0,0 +1,168 @@
+"""Async generation runner: model + dataset -> predictions -> scored report.
+
+The async boundary is exactly "waiting on the model". Data loading and
+scoring stay synchronous (fast, CPU/disk bound); this coroutine fans out
+model calls with a semaphore, streams progress, then hands the collected
+raw strings to the sync evaluate().
+
+    from evalharness.model import run_eval
+    report = asyncio.run(run_eval(ds, 'mock', limit=50))   # offline smoke
+    report = asyncio.run(run_eval(ds, 'openai/http://gpu03:8000/v1?qwen3-8b'))
+"""
+
+import asyncio
+import time
+from typing import Any, Dict, List, Optional, Union
+
+from ..data.dataset import Dataset
+from ..data.sample import ChatMessage, Sample
+from ..eval.recipe import EvalRecipe
+from ..eval.record import EvalReport
+from ..eval.runner import evaluate
+from .adapter import ModelAdapter, resolve_adapter
+from .output import Usage
+
+
+async def generate_predictions(
+    adapter: ModelAdapter,
+    samples: List[Sample],
+    concurrency: int = 32,
+    limit: Optional[int] = None,
+    gen_kwargs: Optional[Dict[str, Any]] = None,
+    progress: bool = True,
+) -> tuple:
+    """Fan out model calls; returns (raws, total_usage).
+
+    Each sample becomes one user message (or its ChatMessage list is used
+    verbatim for multi-turn samples). Tool declarations from sample.tools
+    are passed through so fc/agent recipes degrade gracefully today and
+    agent loops can reuse this adapter untouched.
+    """
+    gen_kwargs = gen_kwargs or {}
+    sem = asyncio.Semaphore(concurrency)
+    total_usage = Usage()
+    done_count = 0
+    t0 = time.time()
+    raws: List[str] = []
+    usages: List[Dict[str, Any]] = []
+
+    async def one(sample: Sample) -> tuple:
+        nonlocal done_count, total_usage
+        messages = ([ChatMessage(role='user', content=sample.input)] if isinstance(sample.input, str)
+                    else list(sample.input))
+        tools = None
+        if sample.tools:
+            tools = [{'name': t.name, 'description': t.description or '',
+                      'parameters': t.parameters} for t in sample.tools]
+        if getattr(adapter, 'name', '') == 'mock' and adapter.extra.get('mode') == 'boxed' \
+                and sample.target not in ('', None):
+            # oracle channel for mock:boxed so full pipelines verify offline
+            messages = messages + [ChatMessage(role='user',
+                                               content=f'MOCKTARGET::{sample.target}')]
+        async with sem:
+            out = await adapter.generate(messages, tools=tools, **gen_kwargs)
+        total_usage = total_usage + out.usage
+        text = out.text
+        if out.tool_calls:  # fc tasks: serialize calls as the prediction
+            import json
+
+            text = (text + '\n' if text else '') + json.dumps(
+                [c.to_openai()['function'] for c in out.tool_calls], ensure_ascii=False)
+        usage = out.usage.model_dump()
+        done_count += 1
+        if progress and (done_count % 20 == 0 or done_count == len(samples)):
+            rate = done_count / max(time.time() - t0, 1e-6)
+            print(f'  [{done_count}/{len(samples)}] {rate:.1f} samples/s '
+                  f'tokens={total_usage.total_tokens}', flush=True)
+        return text, usage
+
+    work = samples[:limit] if limit else samples
+    pairs = await asyncio.gather(*(one(s) for s in work))
+    raws = [p[0] for p in pairs]
+    usages = [p[1] for p in pairs]
+    return raws, usages, total_usage
+
+
+async def run_eval(
+    dataset: Union[Dataset, List[Sample]],
+    model_spec: str,
+    recipe: Optional[EvalRecipe] = None,
+    *,
+    concurrency: int = 32,
+    limit: Optional[int] = None,
+    gen_kwargs: Optional[Dict[str, Any]] = None,
+    judge_spec: Optional[str] = None,
+    judge: Optional[Any] = None,
+    progress: bool = True,
+) -> EvalReport:
+    """Generate + score in one call. Model spec examples:
+    'mock', 'mock:boxed', 'openai/http://gpu03:8000/v1?qwen3-8b', 'deploy:vllm/qwen3-8b'.
+    """
+    adapter = _make_adapter(model_spec)
+    spec = getattr(dataset, 'spec', None)
+    name = spec.name if spec is not None else 'adhoc'
+    if recipe is None:
+        from ..eval.recipe import EvalRecipe, get_eval
+
+        try:
+            recipe = get_eval(name)
+        except KeyError:
+            if name != 'adhoc':
+                raise
+            recipe = EvalRecipe(name='adhoc', extract='identity',
+                                scorers={'acc': {'name': 'exact', 'mode': 'raw'}})
+    samples = list(dataset)[:limit] if limit else list(dataset)
+    if progress:
+        print(f'generating: {adapter} on {len(samples)} samples '
+              f'(concurrency={concurrency})', flush=True)
+    try:
+        raws, usages, usage = await generate_predictions(adapter, samples, concurrency,
+                                                         progress=progress, gen_kwargs=gen_kwargs)
+    finally:
+        await adapter.close()
+    if judge is None and judge_spec:
+        judge_adapter = _make_adapter(judge_spec)
+        judge = _judge_callable(judge_adapter)
+
+    preds = [{'raw': r, 'usage': u} for r, u in zip(raws, usages)]
+    report = evaluate(
+        samples, preds, recipe,
+        model=model_spec,
+        judge=judge,
+        extra_metadata={'gen_input_tokens': usage.input_tokens,
+                        'gen_output_tokens': usage.output_tokens,
+                        'gen_total_tokens': usage.total_tokens},
+    )
+    report.model = model_spec
+    report.dataset = name
+    return report
+
+
+def _make_adapter(spec: str) -> ModelAdapter:
+    """'mock:boxed' -> MockAdapter(mode='boxed'); else resolve_adapter().
+
+    The colon-mode syntax exists ONLY for 'mock': adapter names contain no
+    scheme/colon, so 'mock:xxx' is safe while URLs ('openai/http://...')
+    must never be split on ':'.
+    """
+    base, sep, mode = spec.partition(':')
+    if sep and '/' not in base and base == 'mock':
+        adapter = resolve_adapter('mock')
+        adapter.extra['mode'] = mode or 'echo'
+        return adapter
+    return resolve_adapter(spec)
+
+
+def _judge_callable(judge_adapter: ModelAdapter):
+    async def ask(messages) -> str:
+        out = await judge_adapter.generate([ChatMessage(role='user', content=str(m)) for m in messages]
+                                           if isinstance(messages, list) and messages and isinstance(messages[0], dict)
+                                           else messages)
+        return out.text
+
+    import asyncio
+
+    def sync_ask(messages):
+        return asyncio.run(ask(messages))
+
+    return sync_ask

tests/test_model.py

@@ -0,0 +1,118 @@
+"""Model layer tests: spec parsing, adapters, async runner end-to-end.
+
+Run:  .venv/bin/python tests/test_model.py
+"""
+
+import asyncio
+import json
+import sys
+import threading
+from http.server import BaseHTTPRequestHandler, HTTPServer
+from pathlib import Path
+
+sys.path.insert(0, str(Path(__file__).parent.parent))
+
+from evalharness.data.sample import Sample, ToolInfo  # noqa: E402
+from evalharness.model import MockAdapter, OpenAICompatible, resolve_adapter, run_eval  # noqa: E402
+from evalharness.model.adapter import parse_model_spec  # noqa: E402
+from evalharness.model.runner import _make_adapter  # noqa: E402
+
+
+def test_parse_spec():
+    got = parse_model_spec('openai/http://gpu03:8000/v1?qwen3-8b')
+    assert got == {'adapter': 'openai', 'api_base': 'http://gpu03:8000/v1', 'model': 'qwen3-8b'}
+    assert parse_model_spec('mock') == {'adapter': 'mock', 'api_base': '', 'model': ''}
+
+
+def test_make_adapter_mock_modes():
+    a = _make_adapter('mock:boxed')
+    assert isinstance(a, MockAdapter) and a.extra['mode'] == 'boxed'
+    b = _make_adapter('mock')
+    assert isinstance(b, MockAdapter) and b.extra.get('mode', 'echo') == 'echo'
+    c = _make_adapter('openai/http://127.0.0.1:9/v1?m')
+    assert isinstance(c, OpenAICompatible) and c.api_base == 'http://127.0.0.1:9/v1' and c.model == 'm'
+
+
+def test_mock_tool_mode():
+    out = asyncio.run(MockAdapter().generate([Sample(input='x').input
+                                              and __import__('evalharness.data.sample', fromlist=['ChatMessage']).ChatMessage(role='user', content='x')]))
+    assert out.text == 'x'
+
+
+def _fake_server():
+    class Fake(BaseHTTPRequestHandler):
+        def do_POST(self):
+            body = json.loads(self.rfile.read(int(self.headers['Content-Length'])))
+            msg = body['messages'][-1]['content']
+            tool_calls = []
+            if body.get('tools'):
+                tool_calls = [{'id': 'c1', 'function': {'name': 't1', 'arguments': '{"x": 1}'}}]
+            resp = {'choices': [{'message': {'content': f'echo:{msg}', 'tool_calls': tool_calls},
+                                 'finish_reason': 'tool_calls' if tool_calls else 'stop'}],
+                    'usage': {'prompt_tokens': 3, 'completion_tokens': 5, 'total_tokens': 8},
+                    'model': body['model']}
+            data = json.dumps(resp).encode()
+            self.send_response(200)
+            self.send_header('Content-Type', 'application/json')
+            self.send_header('Content-Length', str(len(data)))
+            self.end_headers()
+            self.wfile.write(data)
+
+        def log_message(self, *a):
+            pass
+
+    srv = HTTPServer(('127.0.0.1', 0), Fake)
+    threading.Thread(target=srv.serve_forever, daemon=True).start()
+    return srv
+
+
+def test_openai_adapter_roundtrip():
+    srv = _fake_server()
+    port = srv.server_address[1]
+    try:
+        rep = asyncio.run(run_eval([Sample(input='hello', target='echo:hello')],
+                                   f'openai/http://127.0.0.1:{port}/v1?fake-m',
+                                   progress=False))
+        r = rep.samples[0]
+        assert 'echo:hello' in r.raw_prediction
+        assert r.usage['total_tokens'] == 8
+    finally:
+        srv.shutdown()
+
+
+def test_tools_pass_through():
+    srv = _fake_server()
+    port = srv.server_address[1]
+    try:
+        s = Sample(input='call it', tools=[ToolInfo(name='f1', parameters={'type': 'object'})])
+        rep = asyncio.run(run_eval([s], f'openai/http://127.0.0.1:{port}/v1?fake-m',
+                                   progress=False))
+        assert '"t1"' in rep.samples[0].raw_prediction  # tool call serialized into prediction
+    finally:
+        srv.shutdown()
+
+
+def test_oracle_mock_pipeline():
+    from evalharness import get_dataset
+
+    ds = get_dataset('gsm8k')
+    rep = asyncio.run(run_eval(ds, 'mock:boxed', limit=50, concurrency=8, progress=False))
+    assert rep.metrics['acc'] == 1.0
+    assert rep.dataset == 'gsm8k'
+    assert rep.metric_groups['run_info']['gen_total_tokens'] == 100
+
+
+if __name__ == '__main__':
+    fails = 0
+    for name, fn in sorted({k: v for k, v in globals().items()
+                            if k.startswith('test_') and callable(v)}.items()):
+        try:
+            fn()
+            print(f'PASS {name}')
+        except AssertionError as e:
+            fails += 1
+            print(f'FAIL {name}: {e}')
+        except Exception as e:
+            fails += 1
+            print(f'ERROR {name}: {type(e).__name__}: {e}')
+    sys.exit(1 if fails else 0)