@molecule/api-equity-prices

Provider-agnostic equity-prices interface for molecule.dev.

Defines the EquityPricesProvider interface for stock / ETF / fund quotes, historical bars, fundamentals, and symbol search. Bond packages (Alpha Vantage, IEX Cloud, Polygon.io, etc.) implement this interface. Application code uses the convenience functions (getQuote, getHistorical, getFundamentals, searchSymbol, listSupportedExchanges) which delegate to the bonded provider.

Quotes carry an explicit ISO 4217 currency so multi-exchange callers can reconcile prices across markets. Symbols and exchange codes are kept as plain strings so providers can support whatever catalogue they expose.

Auto-generated, AI-first package reference for the molecule.dev ecosystem. It is written to be read by coding agents as much as by people, and is generated from this package's source — edit src/index.ts JSDoc, not this file.

Quick Start

import { setProvider, getQuote, getHistorical } from '@molecule/api-equity-prices'
import { provider as alphaVantage } from '@molecule/api-equity-prices-alpha-vantage'

setProvider(alphaVantage)
const quote = await getQuote('AAPL')
const bars = await getHistorical('AAPL', '1y')

Type

core

Installation

npm install @molecule/api-equity-prices @molecule/api-bond @molecule/api-i18n

API

Interfaces

EquityQuote

A single point-in-time equity price quote.

interface EquityQuote {
  /**
   * Equity / ETF / fund ticker symbol.
   */
  symbol: EquitySymbol

  /**
   * Latest traded price (or last close if market is closed), expressed in
   * `currency` as a plain `number` (major units, e.g. dollars).
   */
  price: number

  /**
   * ISO 4217 currency code the `price` is denominated in.
   */
  currency: CurrencyCode

  /**
   * Timestamp the quote was observed.
   */
  ts: Date

  /**
   * Exchange the symbol is listed on. Optional — not every provider exposes
   * the exchange consistently.
   */
  exchange?: ExchangeCode
}

EquityHistoricalBar

A single historical price bar (close-only by default; providers may extend with OHLCV via additional optional fields if useful, but the canonical contract is { ts, close }).

interface EquityHistoricalBar {
  /**
   * Bar timestamp (period start; daily bars are conventionally midnight UTC).
   */
  ts: Date

  /**
   * Closing price for the bar in the symbol's native currency.
   */
  close: number
}

EquityFundamentals

Optional fundamentals snapshot. All fields are optional because providers vary in coverage; consumers MUST treat missing fields as "unknown" rather than zero.

interface EquityFundamentals {
  /**
   * Equity / ETF / fund ticker symbol the fundamentals describe.
   */
  symbol: EquitySymbol

  /**
   * Market capitalization in major units of `currency`, if known.
   */
  marketCap?: number

  /**
   * Trailing price/earnings ratio, if known.
   */
  peRatio?: number

  /**
   * Trailing earnings per share in `currency`, if known.
   */
  eps?: number

  /**
   * Trailing dividend yield as a fraction (e.g. `0.012` for 1.2%), if known.
   */
  dividendYield?: number

  /**
   * Currency the monetary fundamentals are denominated in.
   */
  currency?: CurrencyCode
}

EquitySymbolMatch

A symbol-search result row.

interface EquitySymbolMatch {
  /**
   * Ticker symbol.
   */
  symbol: EquitySymbol

  /**
   * Human-readable security name (e.g. `'Apple Inc.'`).
   */
  name: string

  /**
   * Exchange the symbol is listed on, if known.
   */
  exchange?: ExchangeCode

  /**
   * Currency the security trades in, if known.
   */
  currency?: CurrencyCode
}

EquityPricesProvider

Equity / ETF / fund price + fundamentals provider interface.

All providers (Alpha Vantage, IEX Cloud, Polygon.io, fixtures, etc.) implement this interface. The interface is deliberately minimal so providers with very different upstream APIs can satisfy it identically.

interface EquityPricesProvider {
  /**
   * Returns the latest available quote for `symbol`.
   *
   * @param symbol - Ticker symbol to quote.
   * @returns Latest `EquityQuote`.
   */
  getQuote(symbol: EquitySymbol): Promise<EquityQuote>

  /**
   * Returns historical close-price bars for `symbol` over
   * `range`. Bars are returned in ascending chronological order.
   *
   * @param symbol - Ticker symbol to load history for.
   * @param range - Time range to cover.
   * @returns Array of `EquityHistoricalBar` in ascending order.
   */
  getHistorical(symbol: EquitySymbol, range: EquityHistoricalRange): Promise<EquityHistoricalBar[]>

  /**
   * Returns trailing fundamentals for `symbol`. Providers without
   * fundamentals coverage MAY return an object with only the {@link
   * EquityFundamentals.symbol} field populated.
   *
   * @param symbol - Ticker symbol to load fundamentals for.
   * @returns snapshot.
   */
  getFundamentals(symbol: EquitySymbol): Promise<EquityFundamentals>

  /**
   * Searches the provider's symbol catalogue for matches against
   * `query` (matched against ticker and/or company name).
   *
   * @param query - Free-text search string.
   * @returns Array of `EquitySymbolMatch`, possibly empty.
   */
  searchSymbol(query: string): Promise<EquitySymbolMatch[]>

  /**
   * Lists the exchanges this provider currently supports. Used by callers
   * to determine which markets they can query.
   *
   * @returns Array of exchange identifiers (e.g. `'NASDAQ'`, `'NYSE'`).
   */
  listSupportedExchanges(): Promise<ExchangeCode[]>
}

Types

EquitySymbol

Equity / ETF / fund symbol ticker (e.g. 'AAPL', 'VOO', 'SPY').

Kept as a plain string alias rather than a string-literal union so providers can support whatever set of symbols / exchanges they expose. Use EquityPricesProvider.searchSymbol to discover what a given provider supports at runtime.

type EquitySymbol = string

ExchangeCode

Exchange identifier (e.g. 'NASDAQ', 'NYSE', 'LSE', 'TSE').

Plain string for the same reason as EquitySymbol — providers differ widely on which exchanges they cover.

type ExchangeCode = string

CurrencyCode

ISO 4217 three-letter currency code (e.g. 'USD', 'EUR', 'JPY').

Quotes from a provider may be denominated in any currency the underlying exchange supports.

type CurrencyCode = string

EquityHistoricalRange

Supported historical price ranges.

Providers SHOULD support at least '1d', '1m', and '1y'. Providers MAY throw Error if a requested range is not supported.

type EquityHistoricalRange = '1d' | '5d' | '1m' | '3m' | '6m' | '1y' | '5y' | 'max'

Functions

setProvider(provider)

Registers an equity-prices provider as the active singleton. Called by bond packages (e.g. @molecule/api-equity-prices-alpha-vantage) during application startup.

function setProvider(provider: EquityPricesProvider): void

• provider — The equity-prices provider implementation to bond.

getProvider()

Retrieves the bonded equity-prices provider, throwing if none is configured.

function getProvider(): EquityPricesProvider

Returns: The bonded equity-prices provider.

hasProvider()

Checks whether an equity-prices provider is currently bonded.

function hasProvider(): boolean

Returns: true if an equity-prices provider is bonded.

getQuote(symbol)

Returns the latest available quote for symbol using the bonded provider.

function getQuote(symbol: string): Promise<EquityQuote>

• symbol — Ticker symbol to quote.

Returns: Latest EquityQuote.

getHistorical(symbol, range)

Returns historical close-price bars for symbol over range using the bonded provider. Bars are returned in ascending chronological order.

function getHistorical(symbol: string, range: EquityHistoricalRange): Promise<EquityHistoricalBar[]>

• symbol — Ticker symbol to load history for.
• range — Time range to cover.

Returns: Array of EquityHistoricalBar in ascending order.

getFundamentals(symbol)

Returns trailing fundamentals for symbol using the bonded provider.

function getFundamentals(symbol: string): Promise<EquityFundamentals>

• symbol — Ticker symbol to load fundamentals for.

Returns: snapshot.

searchSymbol(query)

Searches the bonded provider's symbol catalogue for matches against query.

function searchSymbol(query: string): Promise<EquitySymbolMatch[]>

• query — Free-text search string.

Returns: Array of EquitySymbolMatch, possibly empty.

listSupportedExchanges()

Lists the exchanges the bonded provider currently supports.

function listSupportedExchanges(): Promise<string[]>

Returns: Array of exchange identifiers.

Available Providers

Provider	Package
Alpha Vantage Equity Prices	@molecule/api-equity-prices-alpha-vantage
IEX Cloud	@molecule/api-equity-prices-iex
Polygon.io Equity Prices	@molecule/api-equity-prices-polygon

Injection Notes

Requirements

Peer dependencies:

• @molecule/api-bond ^1.0.1
• @molecule/api-i18n ^1.0.1

Runtime Dependencies

• @molecule/api-bond

• @molecule/api-i18n

• Server-side only. Provider API keys are secrets; fetch quotes in API handlers/jobs and serve the UI through the app's own endpoints.

• Cache aggressively. Free market-data tiers are severely rate-limited (some to a few dozen calls per DAY) — a getQuote() per page render exhausts the quota. Cache quotes server-side and refresh on an interval, not per request.

• Symbols and exchanges are provider catalogues, not universal. Resolve user input through searchSymbol() instead of assuming a ticker exists, and store what the provider returned.

• EquityFundamentals fields are optional by contract — treat a missing field as "unknown", never as zero (an absent P/E is not a 0 P/E).

• Quotes carry an explicit ISO 4217 currency — format prices with it; never hardcode $.

• getHistorical(symbol, range) takes an enum range ('1d'…'5y', 'max'); bars return in ascending chronological order.

E2E Tests

Integration checklist — drive the real UI (live preview, no mocks), adapt each item to this app's actual screens/flows, and check every box off one by one. A box you can't check is an integration bug to fix — not a skip:

• A known ticker (e.g. getQuote('AAPL')) renders a PLAUSIBLE quote in the UI — a real price in a sane range, formatted with the quote's own currency (never a hardcoded $), never 0 / null / NaN or a spinner that never resolves.
• Several distinct tickers (e.g. AAPL and MSFT) each render their OWN price — not one shared placeholder or the same number repeated (a stale-cache or wrong-symbol wiring bug).
• If the app charts history, getHistorical(symbol, range) returns an ascending series of { ts, close } that actually draws a line that moves — not an empty array, a flat line, or points in reversed order.
• An invalid / unknown ticker resolves to a clear "not found" in the UI (empty searchSymbol() results, or a caught getQuote error) — never a crash, a blank card, or a NaN price.
• Staleness is honest: the quote's ts is surfaced (a timestamp or a "delayed / last close" label) so an out-of-hours last-close price is NOT presented as a live trade — the UI never dresses stale data up as real-time.
• A provider rate-limit / outage (free tiers cap at a few calls) degrades gracefully to last-known-cached data or an empty state with a message — never a crashed page or a NaN; quotes are cached server-side, not refetched per render.
• The provider API key stays server-side: quotes are served only through the app's own authenticated endpoint, scoped to specific symbols — not an open, unbounded proxy any caller can pass arbitrary tickers/params to.