REST API Reference - DecisionsLayer

Authentication

Base URL: https://api.decisionslayer.com. Public integration endpoints use a workspace API key.

headers.httphttp

X-API-Key: dl_live_...
Content-Type: application/json

Intentionally omitted. Account auth, password recovery, workspace administration, billing, Stripe webhooks, workspace configuration, and UI helper endpoints are not part of the public landing API reference.

Decisions and Outcomes

POST/api/v1/decisions

Logs a decision. external_decision_id is idempotent within a tenant.

Request example

Log a transaction review decisionbash

curl -X POST "$BASE_URL/api/v1/decisions" \
  -H "X-API-Key: $DL_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "external_decision_id": "txn-review-2026-0001",
    "decision_type": "transaction_review",
    "subject": {
      "type": "transaction",
      "id": "txn_123"
    },
    "decision": {
      "action": "review",
      "status": "final"
    },
    "actors": [
      {
        "type": "model",
        "id": "risk-v5",
        "version": "5.2.1"
      }
    ],
    "evidence": [
      {
        "type": "score",
        "key": "risk_score",
        "value": "0.82"
      }
    ],
    "context": {
      "channel": "mobile",
      "region": "US"
    },
    "inputs": {
      "amount": 250,
      "currency": "USD"
    },
    "metadata": {
      "source_system": "payments-api"
    },
    "occurred_at": "2026-05-08T10:00:00Z"
  }'

GET/api/v1/decisions

Lists decisions. Common filters include decision_type, subject_type, subject_id, action, status, actor_type, actor_id, evidence_type, evidence_key, outcome_type, date_from, date_to, page, and page_size.

List recent transaction reviewsbash

curl "$BASE_URL/api/v1/decisions?decision_type=transaction_review&subject_type=transaction&page_size=25" \
  -H "X-API-Key: $DL_API_KEY"

GET/api/v1/decisions/{id}

Gets one decision with actors, evidence, context, inputs, metadata, and attached outcomes.

Get one decisionbash

curl "$BASE_URL/api/v1/decisions/$DECISION_ID" \
  -H "X-API-Key: $DL_API_KEY"

POST /api/v1/decisions/{id}/outcomes

Attaches an outcome when the DecisionsLayer decision ID is known.

Attach review resultbash

curl -X POST "$BASE_URL/api/v1/decisions/$DECISION_ID/outcomes" \
  -H "X-API-Key: $DL_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "external_outcome_id": "outcome-2026-0001",
    "outcome_type": "review_result",
    "outcome_value": "approved",
    "payload": {
      "review_queue": "manual-tier-1",
      "reviewer_id": "agent_42"
    },
    "occurred_at": "2026-05-08T10:04:00Z"
  }'

POST/api/v1/outcomes

Attaches an outcome by external_decision_id or by subject reference.

Attach by external decision IDbash

curl -X POST "$BASE_URL/api/v1/outcomes" \
  -H "X-API-Key: $DL_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "external_decision_id": "txn-review-2026-0001",
    "external_outcome_id": "outcome-2026-0001",
    "outcome_type": "review_result",
    "outcome_value": "approved",
    "payload": {
      "review_queue": "manual-tier-1"
    },
    "occurred_at": "2026-05-08T10:04:00Z"
  }'

Attach by subjectbash

curl -X POST "$BASE_URL/api/v1/outcomes" \
  -H "X-API-Key: $DL_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "subject": {
      "type": "transaction",
      "id": "txn_123"
    },
    "decision_type": "transaction_review",
    "outcome_type": "chargeback",
    "outcome_value": "not_fraud",
    "payload": {
      "case_id": "cb_789"
    },
    "occurred_at": "2026-05-12T15:30:00Z"
  }'

GET /api/v1/subjects/{subjectType}/{subjectId}/timeline

Returns decision and outcome history for a subject.

Get subject timelinebash

curl "$BASE_URL/api/v1/subjects/transaction/txn_123/timeline" \
  -H "X-API-Key: $DL_API_KEY"

Analytics and Observability

GET /api/v1/analytics/dashboard

Returns high-level dashboard metrics.

Get dashboard metricsbash

curl "$BASE_URL/api/v1/analytics/dashboard" \
  -H "X-API-Key: $DL_API_KEY"

GET /api/v1/analytics/effectiveness

Returns effectiveness metrics by evidence, actor, and latency.

Get effectiveness metricsbash

curl "$BASE_URL/api/v1/analytics/effectiveness" \
  -H "X-API-Key: $DL_API_KEY"

GET /api/v1/observability/summary

Returns current observability summary metrics.

Get observability summarybash

curl "$BASE_URL/api/v1/observability/summary?decision_type=transaction_review" \
  -H "X-API-Key: $DL_API_KEY"

GET /api/v1/observability/trends

Returns time-series observability metrics.

Get daily trendsbash

curl "$BASE_URL/api/v1/observability/trends?interval=day&from=2026-05-01T00:00:00Z&to=2026-05-31T23:59:59Z" \
  -H "X-API-Key: $DL_API_KEY"

GET /api/v1/observability/evidence

Returns evidence usage and quality metrics.

Get evidence metricsbash

curl "$BASE_URL/api/v1/observability/evidence?evidence_key=risk_score" \
  -H "X-API-Key: $DL_API_KEY"

GET /api/v1/observability/actors

Returns actor-level observability metrics.

Get model actor metricsbash

curl "$BASE_URL/api/v1/observability/actors?actor_type=model" \
  -H "X-API-Key: $DL_API_KEY"

GET /api/v1/observability/latency

Returns decision and outcome latency metrics.

Get latency metricsbash

curl "$BASE_URL/api/v1/observability/latency?decision_type=transaction_review" \
  -H "X-API-Key: $DL_API_KEY"

Decision Intelligence

These endpoints are available when the workspace plan includes Decision Intelligence.

GET /api/v1/decisions/{id}/quality

Returns quality details for one decision.

Get decision qualitybash

curl "$BASE_URL/api/v1/decisions/$DECISION_ID/quality" \
  -H "X-API-Key: $DL_API_KEY"

GET /api/v1/intelligence/quality-summary

Returns quality summary metrics.

Get quality summarybash

curl "$BASE_URL/api/v1/intelligence/quality-summary?decision_type=transaction_review" \
  -H "X-API-Key: $DL_API_KEY"

GET /api/v1/intelligence/quality-trends

Returns quality trend series.

Get quality trendsbash

curl "$BASE_URL/api/v1/intelligence/quality-trends?from=2026-05-01T00:00:00Z&to=2026-05-31T23:59:59Z" \
  -H "X-API-Key: $DL_API_KEY"

GET /api/v1/intelligence/evidence-correlation

Returns correlations between evidence and outcomes.

Get evidence correlationbash

curl "$BASE_URL/api/v1/intelligence/evidence-correlation?decision_type=transaction_review" \
  -H "X-API-Key: $DL_API_KEY"

GET /api/v1/intelligence/compare/actors

Compares decision actors.

Compare model actorsbash

curl "$BASE_URL/api/v1/intelligence/compare/actors?decision_type=transaction_review" \
  -H "X-API-Key: $DL_API_KEY"

GET /api/v1/intelligence/patterns

Returns detected decision and quality patterns.

Get patternsbash

curl "$BASE_URL/api/v1/intelligence/patterns?decision_type=transaction_review" \
  -H "X-API-Key: $DL_API_KEY"