@cohesionauth/sdk

Save humanity by keeping judgment alive in the age of AI.

Official TypeScript SDK for the COHESION API. COHESION measures whether human oversight of AI is real, durable, and reviewable. The SDK wraps the live scoring, routing, audit-chain, and compliance-rollup endpoints; pair it with an OpenAI, Anthropic, Azure OpenAI, Bedrock, Vertex, or in-house model to instrument every human-AI interaction.

Reference scopes a buyer typically maps the evidence model to: EU AI Act Article 14, Colorado SB 205, Colorado SB 26-189 ADMT, NYC Local Law 144, SR 11-7.

• npm: @cohesionauth/sdk
• License: Apache-2.0
• Requires: Node.js 22.12 or later
• Base URL: https://api.cohesionauth.com (human-readable docs at https://cohesionauth.com/api)

Evaluate COHESION in 30 minutes

The canonical buyer-engineer evaluation path. Each step has a runnable artifact.

1. Curl the unauthenticated root: curl -s https://api.cohesionauth.com/v1 | jq.
2. Get a key at https://cohesionauth.com/pricing (Starter $499/mo via the pricing page; FDP fit-call gated).
3. npm install @cohesionauth/sdk.
4. Score one decision (see Quickstart below).
5. Replay it via curl against the live endpoint: curl https://api.cohesionauth.com/v1/decision/replay/$AI_DECISION_LOG_ID -H "X-API-Key: $COHESION_API_KEY" (no SDK wrapper).
6. Pull a compliance rollup: await cohesion.complianceReport().
7. Verify the audit chain via curl (admin-only, master-key auth, no SDK wrapper): curl https://api.cohesionauth.com/v1/admin/audit/verify-chain -H "X-API-Key: $COHESION_ADMIN_API_KEY".
8. Open https://dashboard.cohesionauth.com and search by request_id.

If any step stalls, email peyton@cohesionauth.com with the failing step and the requestId from the SDK error.

JIS vs DRS, when to use each

DRS routes the decision; JIS scores whether the reviewer is a trustworthy router.

Pilot workflow: score one AI decision end-to-end

The same loop every production integration runs.

1. Operator opens a task; your app records session_id + operator_id.
2. Your app calls the AI provider.
3. Your UI presents the AI recommendation; the SDK instruments the interaction in the background.
4. The operator commits a decision.
5. Your app calls cohesion.score(...); SDK attaches Idempotency-Key automatically.
6. The engine returns the JIS envelope under 100ms p50.
7. Your app stores request_id from the response against the decision. If you are using the DRS gate (cohesion.decisionScore() / gate()), also store the ai_decision_log_id it returns. That is the identifier GET /v1/decision/replay/{ai_decision_log_id} accepts.

Generate an oversight evidence packet

The artifact a design partner gets at pilot close. Two SDK calls plus one curl assemble it. The audit-chain verifier is admin-only (master-key auth) and is not wrapped by the SDK; call it directly with curl.

const report  = await cohesion.complianceReport();
const profile = await cohesion.operatorProfile("analyst-42");

# Admin-only -- uses the scoped master key, NOT the customer scoring key.
curl https://api.cohesionauth.com/v1/admin/audit/verify-chain \
  -H "X-API-Key: $COHESION_ADMIN_API_KEY"

Contents: org-level oversight band distribution, reviewer-level JIS band over time, dimension breakdowns, decay projection, and a tamper-evident audit chain.

Human oversight evidence model

What the SDK produces, conceptually:

1. Observable telemetry from the human-AI interaction (latency, hover, scroll, alternative views, decision class, modification extent).
2. A decision-level score (DRS) that routes the decision BEFORE it reaches the end-user.
3. A reviewer-level score (JIS) that scores whether the reviewer is still functioning as an oversight signal over time.
4. A tamper-evident audit chain that connects telemetry, scores, and the resulting routing into one verifiable record per decision.
5. An evidence packet assembled from the rollup endpoints.

Invisible-by-design: no extension, no survey, no offline assessment.

Example: healthcare intake workflow

A clinical intake nurse uses an AI scribe to draft the chief complaint.

await cohesion.score({
  operator_id: "rn-22871",
  session_id: "intake_2026_05_27_0094",
  domain: "healthcare",
  interaction: {
    ai_recommendation_presented: true,
    time_to_decision_ms: 41200,
    decision: "modified",
    modification_extent: 0.45,
    ai_available: true,
    scenario_type: "standard",
    outcome_correct: null,
    hover_events: 6,
    scroll_depth: 0.92,
    alternative_views_checked: 2,
  },
});

Example: lending decision workflow

A loan officer reviews an AI-recommended credit decision. DRS gates first, then JIS scores the reviewer interaction.

import { gate } from "@cohesionauth/sdk";

const pre = await gate(cohesion, request, null);
if (pre.routing_decision !== "auto") {
  return routeToReviewer(pre);
}
const aiOutput = await provider.complete(request);
await gate(cohesion, request, aiOutput); // post-AI strict gate

// Then JIS-score the reviewer's commit.
await cohesion.score({
  operator_id: "officer-104",
  session_id: "loan_8821",
  domain: "financial",
  interaction: { /* ... */ },
});

Example: HR screening workflow

A recruiter screens AI-shortlisted resumes under NYC Local Law 144. Every accept/reject is logged as an oversight event.

await cohesion.score({
  operator_id: "recruiter-58",
  session_id: "screen_2026_05_27_0044",
  domain: "general",
  interaction: {
    ai_recommendation_presented: true,
    time_to_decision_ms: 27800,
    decision: "rejected",
    modification_extent: 0,
    ai_available: true,
    scenario_type: "standard",
    outcome_correct: null,
    hover_events: 4,
    scroll_depth: 0.7,
    alternative_views_checked: 3,
  },
});

When the city audit window opens, cohesion.complianceReport() returns the aggregate; the admin-only GET /v1/admin/audit/verify-chain endpoint (curl, master-key auth) proves the chain is unbroken.

Install

npm install @cohesionauth/sdk

Quickstart

Get a key:

• New customer: start at https://cohesionauth.com/pricing. Dev is free (raw JSON responses only). Starter is $499/mo or $4,990/yr. The Founding Design Partner cohort is $4,900 one-time, credited 100 percent toward the first year of any annual plan, founder-reviewed via a brief fit call; the cohort closes 2026-07-15. Audited is $1,999/mo or $19,900/yr. Enterprise starts at $50K and is scoped procurement, set up with the founder. Once checkout is live, a completed checkout provisions an org and delivers your API key by email. Key shown once, then rotate from your dashboard.
• Existing customer rotating a key: https://cohesionauth.com/dashboard/api-keys

import { Cohesion } from "@cohesionauth/sdk";

const client = new Cohesion({ apiKey: process.env.COHESION_API_KEY! });

const result = await client.score({
  session_id: "sess_2026_04_22_001",
  operator_id: "analyst-42",
  domain: "financial",
  interaction: {
    ai_recommendation_presented: true,
    time_to_decision_ms: 3400,
    decision: "modified",
    modification_extent: 0.25,
    ai_available: true,
    scenario_type: "standard",
    outcome_correct: null,
    hover_events: 4,
    scroll_depth: 0.9,
    alternative_views_checked: 1,
  },
});

console.log(`JIS ${result.jis} (${result.compliance.band})`);

DRS gate -- the Authorized Inference Gateway

cohesion.gate() wraps a regulated AI call with the Decision Risk Score engine. The contract is strict-gate, fail-closed: the SDK refuses to surface a final AI output unless DRS returned a clean routing_decision envelope.

import {
  Cohesion,
  gate,
  CohesionPolicyBlockedError,
  CohesionRequiresHumanReviewError,
  CohesionMalformedDecisionError,
} from "@cohesionauth/sdk";

const client = new Cohesion({ apiKey: process.env.COHESION_API_KEY! });

// 1. Pre-AI pass: ask DRS whether the input is admissible at all.
const preDecision = await gate(client, request, null);

if (preDecision.routing_decision !== "auto") {
  // must_review / async_review / forced_escalation -- route to a human reviewer
  // BEFORE calling the AI provider. preDecision.review_queue_id is the handle.
  return routeToReviewer(preDecision);
}

// 2. Call the AI provider.
const aiOutput = await provider.complete(request);

// 3. Post-AI pass: ask DRS whether to surface the AI output.
try {
  const postDecision = await gate(client, request, aiOutput);
  // routing_decision === 'auto', no forced escalation -- safe to surface.
  return aiOutput;
} catch (e) {
  if (e instanceof CohesionPolicyBlockedError) {
    // Hard block: never surface this AI output. e.decision.drs_reason_codes
    // and e.decision.policy_evaluation.hard_failures explain why.
    return blockResponse(e);
  }
  if (e instanceof CohesionRequiresHumanReviewError) {
    // Route to reviewer; e.decision.review_queue_id is the handle.
    return routeToReviewer(e.decision);
  }
  if (e instanceof CohesionMalformedDecisionError) {
    // Fail-closed sentinel: DRS returned 2xx but the envelope was malformed.
    // Treat as a hard block. Contact support with e.requestId.
    return blockResponse(e);
  }
  // Network / 5xx / retry-exhausted -> caller MUST treat as fail-closed.
  // Do NOT surface the AI output. The plain `CohesionError`, `ServerError`,
  // `NetworkError` types preserve `requestId` for incident tracing.
  return blockResponse(e);
}

The fail-closed contract on transport failure: if DRS does not return a 2xx envelope (network error, 5xx after retries, abort), gate() re-throws the underlying error unchanged. The caller MUST NOT surface the AI output. Treat any non-resolution as a hard block.

Error class taxonomy:

Pre-AI must_review / async_review / forced escalation return the envelope without throwing -- that branch is the caller's signal to route to a reviewer before the AI call.

See examples/07-live-gate.ts for a runnable end-to-end demonstration.

Oversight receipts -- one signed record per gated decision

cohesion.getReceipt(decisionId) returns a signed, portable oversight receipt for a decision produced by the DRS gate path (gate() / decisionScore()). The receipt serializes the existing decision and human-review records into one tamper-evident artifact: the DRS scores, routing outcome, any human-review entries, and the append-only evidence-chain anchor, all under a single HMAC signature.

Receipts are served by a dedicated worker on receipts.cohesionauth.com (a separate host from the scoring API), configurable via receiptsBaseUrl. Pass the ai_decision_log_id the gate returned.

import { Cohesion } from "@cohesionauth/sdk";

const client = new Cohesion({ apiKey: process.env.COHESION_API_KEY! });

// `decisionId` is the ai_decision_log_id returned by decisionScore() / gate().
const { receipt, signature } = await client.getReceipt(decisionId);

console.log(receipt.chain_anchor.verified_at_issuance); // true on an issued receipt
console.log(signature.receipt_hmac);                    // hex HMAC over the canonical receipt
console.log(signature.key_id);                          // signing-key identifier, e.g. "receipt-v1-..."

The worker re-verifies the decision and review chain anchors at issuance and fails closed rather than emit a receipt that does not verify. It returns 404 for an unknown or cross-tenant decision id (existence is never revealed) and 409 when a decision predates the field-covering evidence chain or fails verification.

Call getReceipt() from server-side code (Node). The receipt host does not currently send CORS headers, so a browser fetch to it is preflight-blocked; the API key belongs on the server regardless. Browser support for this route is tracked separately.

A receipt attaches to the gate path that produces one. The score() (JIS) path does not yet yield a receipt; a future canonical-evidence-record migration will make score() receipt-eligible too (see docs/agentic-os/2026-06-16-evidence-record-unification-migration-plan.md).

Side-by-side

The same request in three forms.

cURL

curl https://api.cohesionauth.com/v1/score \
  -H "X-API-Key: $COHESION_API_KEY" \
  -H "Content-Type: application/json" \
  -H "Idempotency-Key: $(uuidgen)" \
  -d @payload.json

Python

from cohesion import Client

client = Client(api_key=os.environ["COHESION_API_KEY"])
result = client.score(
    session_id="sess_...",
    operator_id="analyst-42",
    domain="financial",
    interaction={...},
)

TypeScript

import { Cohesion } from "@cohesionauth/sdk";

const client = new Cohesion({ apiKey: process.env.COHESION_API_KEY! });
const result = await client.score({ /* ... */ });

5-minute integrations (1.3.1)

Three drop-in patterns. Pick the one that fits your stack.

Express

import express from "express";
import { Cohesion, cohesionExpress } from "@cohesionauth/sdk";

const cohesion = new Cohesion({ apiKey: process.env.COHESION_API_KEY! });
const app = express();

app.use(
  cohesionExpress({
    client: cohesion,
    domain: "financial",
    operatorIdResolver: (req) => String(req.headers["x-user-id"] ?? "anon"),
  }),
);

Next.js (App Router route handler)

import { Cohesion, cohesionNextRoute } from "@cohesionauth/sdk";

const cohesion = new Cohesion({ apiKey: process.env.COHESION_API_KEY! });

export const POST = cohesionNextRoute(
  async (req) => Response.json({ ok: true }),
  {
    client: cohesion,
    domain: "general", // SOC alert-triage maps here per the v1.2 spec
    operatorIdResolver: (req) => req.headers.get("x-user-id") ?? "anon",
  },
);

Decorator (any function -- class method or HOF wrap)

import { measure } from "@cohesionauth/sdk";

const handle = measure({
  client: cohesion,
  domain: "financial",
  operatorIdResolver: ([req]: [{ userId: string }]) => req.userId,
})(originalHandle);

domain is one of healthcare | aviation | financial | legal | pharmaceutical | general. SOC use cases map to general per v1.2 §4 Option A.

For chat-completion patterns (OpenAI / Anthropic / LangChain / Vercel AI), see Provider integrations below or import the chat namespace:

import { chat } from "@cohesionauth/sdk";
const wrapped = chat.wrapOpenAI(openai, cohesion, ctx);

Six full integration examples live under examples/.

Client options

new Cohesion({
  apiKey: string,                                  // required
  baseUrl?: string,        // default "https://api.cohesionauth.com"
  receiptsBaseUrl?: string, // default "https://receipts.cohesionauth.com" (oversight receipts)
  timeout?: number,        // default 30000 ms
  maxRetries?: number,     // default 3
  logger?: Logger,         // default createDefaultLogger()
  enableTelemetry?: boolean, // default false (opt-in Sentry)
});

receiptsBaseUrl configures the host for getReceipt(). Oversight receipts are served by a dedicated worker on receipts.cohesionauth.com, a separate host from the scoring API base; only getReceipt() uses it. Every other method targets baseUrl.

Method reference

AI-provider wrappers

Instrument OpenAI, Anthropic, Azure OpenAI, Vercel AI SDK, or LangChain.

import OpenAI from "openai";
import { Cohesion, wrapOpenAI } from "@cohesionauth/sdk";

const cohesion = new Cohesion({ apiKey: process.env.COHESION_API_KEY! });
const openai = wrapOpenAI(new OpenAI(), cohesion, {
  operatorId: "analyst-42",
  sessionId: "sess_...",
  domain: "financial",
});

const { response, recordDecision } = await openai.chat.completions.create({
  model: "gpt-4",
  messages: [{ role: "user", content: "Draft SAR narrative" }],
});

// Present `response` to the human. After they decide:
const score = await recordDecision({
  decision: "modified",
  modificationExtent: 0.3,
});

Equivalent helpers: wrapAnthropic, wrapAzureOpenAI, vercelAIMiddleware, langChainHandler.

Errors

Every SDK error carries requestId and nextStep.

import { RateLimitError } from "@cohesionauth/sdk";

try {
  await client.score(req);
} catch (err) {
  if (err instanceof RateLimitError) {
    console.log(`Retry in ${err.retryAfter}s. Hint: ${err.nextStep}`);
  } else {
    throw err;
  }
}

CLI

npx cohesion score --operator-id analyst-42 --from-file payload.json
# or via stdin:
cat payload.json | npx cohesion score --operator-id analyst-42 --from-file -

Retry and idempotency

• Exponential backoff with full jitter. Default max 3 retries.
• Retries only on 429 and 5xx. All 4xx (except 429) fail fast.
• Honors Retry-After header (integer seconds or HTTP-date).
• Every POST auto-populates Idempotency-Key with a UUIDv4 so retries are safe to replay.

SDK parity matrix

Every documented endpoint is reachable from the TypeScript SDK, the Python SDK, and the dashboard. Operator-only paths (key rotation, audit log inspection) are read-write in the SDKs and read in the dashboard.

Full 50-endpoint catalog at the OpenAPI schema.

Endpoint status classification

Every endpoint is tagged with one of four maturity classifications.

The Production class covers the entire surface listed in the parity matrix above. Beta endpoints are documented in release notes; Admin endpoints are tagged in the OpenAPI schema with x-cohesion-class: admin.

Errors and recovery

Every failure mode has a documented recovery path. Catch by class, never by string match.

Every error carries requestId and nextStep. The CohesionError base is the safe fallback catch.

Compliance boundaries

What the SDK helps customers prove, and what it does NOT prove.

The SDK measures:

• Whether a named human reviewer was present at the moment of decision.
• Whether the reviewer exercised independent judgment, or rubber-stamped.
• Whether the decision was risky enough to require an additional human, an async review, or a hard block.
• Whether the reviewer's oversight quality is degrading over time.
• Whether the entire interaction is reconstructable from a tamper-evident audit chain.

The SDK does NOT:

• Render legal opinions or determine regulatory conformance on a customer's behalf.
• Replace internal model-risk-management or model-validation processes.
• Score the underlying AI model's correctness or bias.
• Operate as a certification body.

Buyers and their counsel are responsible for mapping the evidence model to specific regulatory obligations.

Data handling and retention

• Transport: TLS 1.3 from your environment to api.cohesionauth.com.
• Storage region: Cloudflare D1 in the customer's contracted region (EU customers on EU edge; US customers on US edge).
• Retention windows: Telemetry and score envelopes: 13 months default, configurable per contract. Audit chain: indefinite (a chain cannot be truncated without breaking proof).
• Redaction: The default logger redacts API keys (pattern ck_live_*) and operator_id values before emit. Free-text prompt content is NEVER stored by the engine.
• Export: client.complianceReport() + client.adminAuditLog() are SDK-callable and downloadable.

Audit trail example

A synthetic but realistic excerpt of the chain returned by GET /v1/admin/audit/verify-chain (admin-only, master-key auth, curl-only -- not wrapped by the SDK). Three consecutive decisions; the chain head proves none were silently dropped or rewritten.

{
  "chain_head": "sha256:a13c…f902",
  "verified": true,
  "entries": [
    {
      "request_id": "req_01HXG7K9Z2W4M6P8B0A2C4E6F8",
      "timestamp": "2026-05-27T14:08:42.318Z",
      "operator_id_hash": "h_e2a9…",
      "decision_class": "modified",
      "drs_routing": "auto",
      "jis_band": "Strong",
      "prev_hash": "sha256:9b71…a004",
      "this_hash": "sha256:c84d…ee19"
    },
    {
      "request_id": "req_01HXG7KCV4Y2T8M0R6E3K1Q9P2",
      "timestamp": "2026-05-27T14:10:01.044Z",
      "operator_id_hash": "h_e2a9…",
      "decision_class": "rejected",
      "drs_routing": "must_review",
      "jis_band": "Strong",
      "prev_hash": "sha256:c84d…ee19",
      "this_hash": "sha256:1f02…7733"
    },
    {
      "request_id": "req_01HXG7KFM8N0Q3D5W2A8H6Y1B6",
      "timestamp": "2026-05-27T14:11:55.610Z",
      "operator_id_hash": "h_e2a9…",
      "decision_class": "accepted",
      "drs_routing": "auto",
      "jis_band": "Adequate",
      "prev_hash": "sha256:1f02…7733",
      "this_hash": "sha256:a13c…f902"
    }
  ]
}

Each entry's this_hash derives from its content plus the previous entry's hash. The chain head is the cryptographic summary of every decision in-window.

Changelog and versioning policy

Semver. The /v1 prefix is the major-version contract; breaking changes ship under /v2 with a 12-month overlap and Deprecation plus Sunset response headers per RFC 8594.

• Backward-compatible additions (new endpoints, new optional fields) ship in minor releases, no advance notice required.
• Deprecations ship with Deprecation and Sunset response headers, minimum 12 months before removal.
• SDK versioning follows API versioning. Patch releases for engine fixes; minor releases for new endpoints; major releases only when the API major changes.
• Full release notes: cohesionauth.com/changelog.

Environment variables

Logging and redaction

The default logger redacts API keys (ck_live_*) and operator_id values before emit. Set COHESION_LOG_FORMAT=json for structured output suitable for Datadog, Sentry, or Cloudflare Logpush.

License

Apache License 2.0. See LICENSE and NOTICE.

The COHESION Judgment Independence Score methodology, scoring engine, and intervention protocol are patent-pending.