> ## Documentation Index
> Fetch the complete documentation index at: https://docs.keplerinsights.us/llms.txt
> Use this file to discover all available pages before exploring further.

# GET /v1/signals

> The 67-signal manifest. What every score is composed of.

A read-only manifest of every signal the engine evaluates. Use it to render bucket / category breakdowns and to look up labels + descriptions for stored `signal_scores` keys.

## When to use it

* Building a UI that lists a company's signal scores by category.
* Documenting your integration ("these 17 signals contributed most to this score").
* Periodic snapshot — fetch once, cache locally, refresh weekly. The manifest changes only on engine releases.

## Response shape

```json theme={null}
{
  "version": "2026-05-12",
  "signals": [
    {
      "key": "founder_years_experience",
      "label": "Founder years of experience",
      "bucket": "team_structure",
      "category": "founding_team",
      "weight": 12.5,
      "actionability": "immutable",
      "description": "Total professional years across the founding team. Sourced from professional employment data with AI enrichment fallback."
    },
    ...
  ]
}
```

## Fields

* **`key`** — stable identifier. Matches the keys in stored `signal_scores` maps. Don't render this directly; use `label`.
* **`label`** — human-readable name.
* **`bucket`** — one of `team_structure`, `market_position`, `momentum_tailwinds`, `financial_health`.
* **`category`** — finer grouping inside the bucket.
* **`weight`** — relative weight in its category. Categories sum to 100 within their parent bucket; signals sum to 100 within their parent category.
* **`actionability`** — `actionable` (a founder can change this in months), `slow_actionable` (years), or `immutable` (e.g. academic background, prior exits).
* **`description`** — one-sentence narrative of what the signal measures.

## Identical in sandbox and live

The manifest is deterministic content — `ki_test_` and `ki_live_` keys both return the same JSON. The response does **not** carry a `mode: "sandbox"` field, by design (no canned-vs-real distinction to make).

## When to refresh

The manifest changes when:

1. Kepler adds a new signal (rare; major engine version bump).
2. Kepler retires a signal (e.g. `competitor_hq_distribution` was removed pre-launch).
3. Weights are tuned (frequent — but the schema stays the same).

The top-level `version` field is a date string and bumps on every change. Compare it to your cached value to decide whether to refresh.


## OpenAPI

````yaml GET /v1/signals
openapi: 3.1.0
info:
  title: Kepler Insights API
  version: 1.0.0
  summary: Curated company-scoring intelligence over a 67-signal engine.
  description: >
    The Kepler Insights API exposes a curated subset of the Kepler scoring
    engine

    over a stable REST surface. Every score is a composite over 67 signals
    organized

    into 4 buckets (Team & Structure, Market Position, Momentum & Tailwinds,

    Financial Health), with a separate scale premium that lifts established

    companies whose underlying fundamentals justify a higher tier.


    **Authentication.** All requests require a single header: `X-API-Key`.

    Keys are issued from the developer console at
    `https://console.keplerinsights.us`.


    **Sandbox.** Test keys prefixed `ki_test_` accept only the four canned

    domains (`acme.test`, `unicorn.test`, `struggling.test`, `cohort.test`),

    never invoke fetchers, and return deterministic responses tagged with

    `mode: sandbox`. Live keys prefixed `ki_live_` reject test domains and

    run against the real engine.


    **Cold vs cached.** `GET /v1/score/{domain}` is always cached (404 if no

    recent record exists). `POST /v1/score` decides per-call based on your

    tier's freshness window: a fresh record returns inline (`200`), a stale

    or missing one queues a cold pipeline run and returns `202` with a

    `job_id` to poll. Cold spend is bounded by per-tier monthly caps +

    circuit breakers.
  contact:
    name: Kepler Insights API support
    email: noah@keplerinsights.us
  license:
    name: Proprietary
servers:
  - url: https://api.keplerinsights.us
    description: Production
security:
  - apiKey: []
tags:
  - name: scoring
    description: Score a company and retrieve the latest result.
  - name: history
    description: Time-series of past scoring runs for a single company.
  - name: company
    description: Per-company analytics (cohort, confidence).
  - name: universe
    description: Distribution + movers across the full scored universe.
  - name: meta
    description: Signal manifest + caller usage + async job tracking.
paths:
  /v1/signals:
    get:
      tags:
        - meta
      summary: The 67-signal schema manifest.
      description: |
        Read-only manifest of every signal the engine scores. Use to render
        bucket / category breakdowns alongside `signal_scores` from a stored
        record. Identical content in sandbox + live (no `mode` field).
      operationId: getSignals
      responses:
        '200':
          description: Signals manifest.
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/SignalsManifest'
        '401':
          $ref: '#/components/responses/Unauthorized'
components:
  schemas:
    SignalsManifest:
      type: object
      properties:
        version:
          type: string
        signals:
          type: array
          items:
            $ref: '#/components/schemas/Signal'
    Signal:
      type: object
      properties:
        key:
          type: string
          example: founder_years_experience
        label:
          type: string
        bucket:
          type: string
          enum:
            - team_structure
            - market_position
            - momentum_tailwinds
            - financial_health
        category:
          type: string
        weight:
          type: number
        actionability:
          type: string
          enum:
            - actionable
            - slow_actionable
            - immutable
        description:
          type: string
    ErrorResponse:
      type: object
      properties:
        error:
          type: string
          example: unauthorized
        message:
          type: string
        reason:
          type: string
          description: Additional context for rate-limit responses.
  responses:
    Unauthorized:
      description: Missing or invalid `X-API-Key`.
      content:
        application/json:
          schema:
            $ref: '#/components/schemas/ErrorResponse'
  securitySchemes:
    apiKey:
      type: apiKey
      in: header
      name: X-API-Key
      description: >
        Live keys are prefixed `ki_live_`, test keys `ki_test_`. Issue + revoke

        keys at https://console.keplerinsights.us. Never embed a key in
        client-side

        code — every endpoint is backend-to-API only.

````