@corbits/system-one

Typed choice, score and yes/no decisions about a JSON state from TypeSafe's Jev model, returned as a validated result or a typed fallback. An inference provider for Corbits and Interchange agents: registers as an @intx/inference adapter, and also works standalone through evaluate().

Why @corbits/system-one?

1. Typed decisions, not free text. You send questions with ids; you get back one validated decision per id, with probabilities and confidence. No prompt parsing.
2. Failures are data. A missing key, timeout, HTTP error or bad body returns a FallbackResult with a reason, so a gate can fail closed without a try. Only invalid caller input throws.
3. One call, many questions. Every question in a list goes out in one POST, bounded by a 1.5 s default timeout.

It evaluates structured state against questions. For open-ended chat completions, use a general inference provider such as @corbits/openai-responses.

Install

bun add @corbits/system-one @intx/inference@^0.4.0 @intx/types@^0.4.0

Runs on Bun >= 1.2 or Node >= 24.

Quickstart

Needs TYPESAFE_API_KEY set.

import { evaluate } from "@corbits/system-one";

const result = await evaluate({
  state: { action: "deploy", env: "production" },
  questions: [
    {
      id: "escalate",
      type: "boolean",
      instructions: "Must this request be escalated for human approval?",
    },
  ],
});

console.log(result.fallback ? result.reason : result.decisions);

On success it prints one decision per question, or the fallback reason on failure:

[{ id: "escalate", type: "noul", noul: 0.91 }];

Boolean questions answer as noul, a probability from 0 to 1 that the answer is yes.

Where it fits

Interchange runs AI agents as principals (accounts that hold their own identity, permissions and credentials). Corbits packages add what an agent product needs around it.

• Runs in: the agent sidecar (the runtime next to each agent), or any process. evaluate() needs no Interchange runtime.
• Plugs into: the @intx/inference adapter registry, as the adapter for the corbits-system-one provider id.
• Pairs with: @corbits/openai-responses and @corbits/ollama-adapter, the other Corbits inference providers.

Reference

Export	Description
evaluate(input, options?)	Runs one evaluation. Returns EvaluateResult: decisions or a FallbackResult.
createSystemOneAdapter(config?)	Returns a ProviderAdapter for runInference. config is an EvaluateConfig.
SYSTEM_ONE_PROVIDER	The "corbits-system-one" provider id.
DEFAULT_TIMEOUT_MS	1500, the default timeoutMs.
SystemOneError	Thrown for invalid input or a custom endpoint without a url.
SystemOneTelemetryEvent	Schema and type for events passed to onTelemetry.
EvaluateOptions, EvaluateDeps	Types for options: onTelemetry, and deps: { fetch, scheduler }.

Question, QuestionList, Decision, EvaluateInput, EvaluateConfig, EndpointConfig, EvaluateResult and FallbackResult are exported as arktype schemas and types.

Questions

type	Fields	Decision fields
choice	instructions, criteria (option name → description or null, 1–255 options)	choice, probabilities, confidence
score	instructions, criteria (2–10 descriptions)	score, legend, probabilities, confidence
boolean	instructions, optional criteria: { true?, false? }	noul
noul	Same as boolean	noul

Every question has an id, unique within the list.

Config

input.config for evaluate, or the argument to createSystemOneAdapter:

Field	Type	Default	Description
endpoint	EndpointConfig	{ kind: "official" }	official, gateway, or custom with a url. Each takes an optional model.
timeoutMs	number	1500	Bound for the whole round trip.
apiKey	string	from the environment	Overrides the environment key.

Endpoints and keys

kind	URL	Default model	Key from the environment
official	https://api.typesafe.ai/v1/systemone	jev-latest	TYPESAFE_API_KEY
gateway	https://ai-gateway.vercel.sh/typesafe/v1/systemone	typesafe-ai/jev	AI_GATEWAY_API_KEY, then VERCEL_OIDC_TOKEN
custom	url	typesafe-ai/jev	SYSTEM_ONE_API_KEY

SYSTEM_ONE_API_KEY is also a supported alias on every endpoint, read after the endpoint's own key.

Fallback reasons

reason	When
no-key	No key in apiKey or the environment. No request is sent.
timeout	The round trip, including the body read, exceeds timeoutMs.
network	The request fails before a response.
http-error	Non-2xx response. httpStatus holds the status.
parse-error	The body is not JSON or fails validation.

detail carries the underlying message.

Using with Interchange

Register the adapter under SYSTEM_ONE_PROVIDER and pass questions per call in providerOptions.systemOne ({ state?, questions? }). Without state, the adapter sends the transcript text as state. Without questions, it asks one boolean question with id response.

import { createDependencies, runInference } from "@intx/inference";
import {
  createSystemOneAdapter,
  SYSTEM_ONE_PROVIDER,
  type QuestionList,
} from "@corbits/system-one";

const deps = createDependencies({
  has: (provider) => provider === SYSTEM_ONE_PROVIDER,
  resolve: () => createSystemOneAdapter(),
});

const questions = [
  {
    id: "escalate",
    type: "boolean",
    instructions: "Must this request be escalated for human approval?",
  },
] satisfies QuestionList;

let seq = 0;
for await (const event of runInference({
  deps,
  source: {
    id: "system-one",
    provider: SYSTEM_ONE_PROVIDER,
    baseURL: "https://api.typesafe.ai/v1/systemone",
    credentialId: "TYPESAFE_API_KEY",
    model: "jev-latest",
  },
  turns: [
    {
      role: "user",
      timestamp: Date.now(),
      content: [{ type: "text", text: "Deploy to production?" }],
    },
  ],
  inferenceOptions: { providerOptions: { systemOne: { questions } } },
  nextSeq: () => seq++,
  readMaterial: (id) => {
    const secret = process.env[id];
    if (secret === undefined) throw new Error(`${id} is not set`);
    return { secret };
  },
})) {
  if (event.type === "inference.text.delta")
    console.log(JSON.parse(event.data.token));
}

The adapter emits one inference.text.delta per decision, whose token is the decision as JSON, then an inference.usage event. The harness supplies the credential through readMaterial and owns retries. A malformed response body is a ProtocolMismatchError, not a fallback.

Upgrading from 0.1

• HttpError, NetworkError and TimeoutError are removed. Transport failures return a FallbackResult.
• A 2xx body that is not JSON is parse-error (was network). A timeout during the body read is timeout.
• recordTelemetryEvent and drainTelemetryEvents are removed. Pass evaluate(input, { onTelemetry }).
• Wire helpers, quirks presets, JsonRecord, Confidence and the env-var name constants are no longer exported.
• A custom endpoint without a model sends typesafe-ai/jev.
• Peers are @intx/inference and @intx/types ^0.4.0.
• Environment variables are unchanged, including SYSTEM_ONE_API_KEY.

License

LGPL-2.1-only