zero-config planoai up: synthesize pass-through proxy when no config file

cli/planoai/defaults.py

@@ -0,0 +1,167 @@
+"""Default config synthesizer for zero-config ``planoai up``.
+
+When the user runs ``planoai up`` in a directory with no ``config.yaml`` /
+``plano_config.yaml``, we synthesize a pass-through config that covers the
+common LLM providers and auto-wires OTel export to ``localhost:4317`` so
+``planoai obs`` works out of the box.
+
+Auth handling:
+- If the provider's env var is set, bind ``access_key: $ENV_VAR``.
+- Otherwise set ``passthrough_auth: true`` so the client's own Authorization
+  header is forwarded. No env var is required to start the proxy.
+"""
+
+from __future__ import annotations
+
+import os
+from dataclasses import dataclass
+
+
+DEFAULT_LLM_LISTENER_PORT = 12000
+# plano_config validation requires an http:// scheme on the OTLP endpoint.
+DEFAULT_OTLP_ENDPOINT = "http://localhost:4317"
+
+
+@dataclass(frozen=True)
+class ProviderDefault:
+    name: str
+    env_var: str
+    base_url: str
+    model_pattern: str
+    # Only set for providers whose prefix in the model pattern is NOT one of the
+    # built-in SUPPORTED_PROVIDERS in cli/planoai/config_generator.py. For
+    # built-ins, the validator infers the interface from the model prefix and
+    # rejects configs that set this field explicitly.
+    provider_interface: str | None = None
+
+
+# Keep ordering stable so synthesized configs diff cleanly across runs.
+PROVIDER_DEFAULTS: list[ProviderDefault] = [
+    ProviderDefault(
+        name="openai",
+        env_var="OPENAI_API_KEY",
+        base_url="https://api.openai.com/v1",
+        model_pattern="openai/*",
+    ),
+    ProviderDefault(
+        name="anthropic",
+        env_var="ANTHROPIC_API_KEY",
+        base_url="https://api.anthropic.com/v1",
+        model_pattern="anthropic/*",
+    ),
+    ProviderDefault(
+        name="gemini",
+        env_var="GEMINI_API_KEY",
+        base_url="https://generativelanguage.googleapis.com/v1beta",
+        model_pattern="gemini/*",
+    ),
+    ProviderDefault(
+        name="groq",
+        env_var="GROQ_API_KEY",
+        base_url="https://api.groq.com/openai/v1",
+        model_pattern="groq/*",
+    ),
+    ProviderDefault(
+        name="deepseek",
+        env_var="DEEPSEEK_API_KEY",
+        base_url="https://api.deepseek.com/v1",
+        model_pattern="deepseek/*",
+    ),
+    ProviderDefault(
+        name="mistral",
+        env_var="MISTRAL_API_KEY",
+        base_url="https://api.mistral.ai/v1",
+        model_pattern="mistral/*",
+    ),
+    # DigitalOcean Gradient is OpenAI-compatible and `do` is not in the built-in
+    # SUPPORTED_PROVIDERS list, so we must provide provider_interface explicitly.
+    ProviderDefault(
+        name="do",
+        env_var="DO_API_KEY",
+        base_url="https://inference.do-ai.run/v1",
+        model_pattern="do/*",
+        provider_interface="openai",
+    ),
+]
+
+
+@dataclass
+class DetectionResult:
+    with_keys: list[ProviderDefault]
+    passthrough: list[ProviderDefault]
+
+    @property
+    def summary(self) -> str:
+        parts = []
+        if self.with_keys:
+            parts.append(
+                "env-keyed: " + ", ".join(p.name for p in self.with_keys)
+            )
+        if self.passthrough:
+            parts.append(
+                "pass-through: " + ", ".join(p.name for p in self.passthrough)
+            )
+        return " | ".join(parts) if parts else "no providers"
+
+
+def detect_providers(env: dict[str, str] | None = None) -> DetectionResult:
+    env = env if env is not None else dict(os.environ)
+    with_keys: list[ProviderDefault] = []
+    passthrough: list[ProviderDefault] = []
+    for p in PROVIDER_DEFAULTS:
+        val = env.get(p.env_var)
+        if val:
+            with_keys.append(p)
+        else:
+            passthrough.append(p)
+    return DetectionResult(with_keys=with_keys, passthrough=passthrough)
+
+
+def synthesize_default_config(
+    env: dict[str, str] | None = None,
+    *,
+    listener_port: int = DEFAULT_LLM_LISTENER_PORT,
+    otel_endpoint: str = DEFAULT_OTLP_ENDPOINT,
+) -> dict:
+    """Build a pass-through config dict suitable for validation + envoy rendering.
+
+    The returned dict can be dumped to YAML and handed to the existing `planoai up`
+    pipeline unchanged.
+    """
+    detection = detect_providers(env)
+
+    def _entry(p: ProviderDefault, base: dict) -> dict:
+        row: dict = {"name": p.name, "model": p.model_pattern, "base_url": p.base_url}
+        if p.provider_interface is not None:
+            row["provider_interface"] = p.provider_interface
+        row.update(base)
+        return row
+
+    model_providers: list[dict] = []
+    for p in detection.with_keys:
+        model_providers.append(_entry(p, {"access_key": f"${p.env_var}"}))
+    for p in detection.passthrough:
+        model_providers.append(_entry(p, {"passthrough_auth": True}))
+
+    # We intentionally don't mark any provider as `default: true` here:
+    # the validator rejects wildcard models (e.g. `openai/*`) as defaults, and
+    # all our entries are wildcards. Clients should prefix model names (e.g.
+    # `openai/gpt-4o-mini`, `do/router:software-engineering`); the wildcard
+    # matcher routes them to the correct provider.
+
+    return {
+        "version": "v0.4.0",
+        "listeners": [
+            {
+                "name": "llm",
+                "type": "model",
+                "port": listener_port,
+                "address": "0.0.0.0",
+            }
+        ],
+        "model_providers": model_providers,
+        "tracing": {
+            "random_sampling": 100,
+            "opentracing_grpc_endpoint": otel_endpoint,
+        },
+    }

cli/planoai/main.py

@@ -328,12 +328,30 @@ def up(file, path, foreground, with_tracing, tracing_port, docker, verbose):
         # Use the utility function to find config file
         plano_config_file = find_config_file(path, file)
 
-        # Check if the file exists
+        # Zero-config fallback: when no user config is present, synthesize a
+        # pass-through config that covers the common LLM providers and
+        # auto-wires OTel export to ``planoai obs``. See cli/planoai/defaults.py.
         if not os.path.exists(plano_config_file):
-            console.print(
-                f"[red]✗[/red] Config file not found: [dim]{plano_config_file}[/dim]"
+            import yaml
+
+            from planoai.defaults import (
+                detect_providers,
+                synthesize_default_config,
+            )
+
+            detection = detect_providers()
+            cfg_dict = synthesize_default_config()
+
+            default_dir = os.path.expanduser("~/.plano")
+            os.makedirs(default_dir, exist_ok=True)
+            synthesized_path = os.path.join(default_dir, "default_config.yaml")
+            with open(synthesized_path, "w") as fh:
+                yaml.safe_dump(cfg_dict, fh, sort_keys=False)
+            plano_config_file = synthesized_path
+            console.print(
+                f"[dim]No plano config found; using defaults ({detection.summary}). "
+                f"Listening on :12000, tracing -> http://localhost:4317.[/dim]"
             )
-            sys.exit(1)
 
         if not docker:
             from planoai.native_runner import native_validate_config

cli/test/test_defaults.py

@@ -0,0 +1,71 @@
+from pathlib import Path
+
+import jsonschema
+import yaml
+
+from planoai.defaults import (
+    PROVIDER_DEFAULTS,
+    detect_providers,
+    synthesize_default_config,
+)
+
+
+_SCHEMA_PATH = Path(__file__).parents[2] / "config" / "plano_config_schema.yaml"
+
+
+def _schema() -> dict:
+    return yaml.safe_load(_SCHEMA_PATH.read_text())
+
+
+def test_zero_env_vars_produces_pure_passthrough():
+    cfg = synthesize_default_config(env={})
+    assert cfg["version"] == "v0.4.0"
+    assert cfg["listeners"][0]["port"] == 12000
+    for provider in cfg["model_providers"]:
+        assert provider.get("passthrough_auth") is True
+        assert "access_key" not in provider
+    # All known providers should be listed.
+    names = {p["name"] for p in cfg["model_providers"]}
+    assert "do" in names
+    assert "openai" in names
+    assert "anthropic" in names
+
+
+def test_env_keys_promote_providers_to_env_keyed():
+    cfg = synthesize_default_config(
+        env={"OPENAI_API_KEY": "sk-1", "DO_API_KEY": "do-1"}
+    )
+    by_name = {p["name"]: p for p in cfg["model_providers"]}
+    assert by_name["openai"].get("access_key") == "$OPENAI_API_KEY"
+    assert by_name["openai"].get("passthrough_auth") is None
+    assert by_name["do"].get("access_key") == "$DO_API_KEY"
+    # Unset env keys remain pass-through.
+    assert by_name["anthropic"].get("passthrough_auth") is True
+
+
+def test_detection_summary_strings():
+    det = detect_providers(env={"OPENAI_API_KEY": "sk", "DO_API_KEY": "d"})
+    summary = det.summary
+    assert "env-keyed" in summary and "openai" in summary and "do" in summary
+    assert "pass-through" in summary
+
+
+def test_tracing_block_points_at_local_console():
+    cfg = synthesize_default_config(env={})
+    tracing = cfg["tracing"]
+    assert tracing["opentracing_grpc_endpoint"] == "http://localhost:4317"
+    # random_sampling is a percentage in the plano config — 100 = every span.
+    assert tracing["random_sampling"] == 100
+
+
+def test_synthesized_config_validates_against_schema():
+    cfg = synthesize_default_config(env={"OPENAI_API_KEY": "sk"})
+    jsonschema.validate(cfg, _schema())
+
+
+def test_provider_defaults_do_is_configured():
+    by_name = {p.name: p for p in PROVIDER_DEFAULTS}
+    assert "do" in by_name
+    assert by_name["do"].env_var == "DO_API_KEY"
+    assert by_name["do"].base_url == "https://inference.do-ai.run/v1"
+    assert by_name["do"].model_pattern == "do/*"

cli/uv.lock

@@ -337,7 +337,7 @@ wheels = [
 
 [[package]]
 name = "planoai"
-version = "0.4.18"
+version = "0.4.19"
 source = { editable = "." }
 dependencies = [
     { name = "click" },