@midlyr/sdk-js

Thin TypeScript SDK for MidLyr Enterprise REST APIs.

This package intentionally owns only shared API-calling behavior. Future MCP and CLI packages should depend on the SDK through the public @midlyr/sdk-js export instead of duplicating REST transport code.

Install

npm install @midlyr/sdk-js
pnpm add @midlyr/sdk-js
yarn add @midlyr/sdk-js
bun add @midlyr/sdk-js

Create a client

import { Midlyr } from "@midlyr/sdk-js";

const midlyr = new Midlyr({
  apiKey: process.env.MIDLYR_API_KEY!,
  // Override for staging, local development, or private deployments.
  baseUrl: "https://api.midlyr.com",
});

Requests authenticate with the x-api-key header.

Regulation API

const page = await midlyr.regulations.list({
  query: "fair lending",
  jurisdictions: "us-federal",
  limit: 25,
});

const details = await midlyr.regulations.get(page.results[0]!.id);

const content = await midlyr.regulations.getContent(page.results[0]!.id, {
  limit: 4_000,
});

console.log(content.regulation.title, content.content.text);

// Vector-search the corpus and get back the top relevant chunks grouped by
// parent regulation. Pure retrieval — no LLM is invoked.
const { results } = await midlyr.regulations.query({
  query: "provisional credit timing requirements",
  limit: 5,
  filters: { authorities: ["cfpb"] },
});

for (const citation of results) {
  console.log(citation.regulation.title);
  for (const chunk of citation.chunks) {
    console.log(chunk.sectionPath, chunk.text);
  }
}

Analysis APIs

const response = await midlyr.analysis.screen({
  content: { type: "text", text: "Get 0% APR for life!" },
  scenario: "marketing_asset",
});

const job = await midlyr.jobs.get(response.id);

Job API

The SDK exposes jobs.list(query) and jobs.get(id). Jobs use a discriminated union on status: "running", "succeeded", or "failed". It does not provide a polling helper; MCP and CLI layers can decide their own polling or display behavior later.

Timeout and retries

The SDK uses native fetch and has no runtime HTTP-client dependency. Configure timeout and safe retries globally:

const midlyr = new Midlyr({
  apiKey: process.env.MIDLYR_API_KEY!,
  timeoutMs: 30_000,
  maxRetries: 1,
});

You can also override them per request:

await midlyr.regulations.list({ query: "Regulation B" }, { timeoutMs: 10_000, maxRetries: 2 });

Retries are intentionally conservative:

• safe GET requests may retry network failures, timeouts, and HTTP 408, 429, 500, 502, 503, or 504 responses;
• mutating POST requests are not retried by default until the API supports an idempotency strategy;
• Retry-After is respected when the API returns it.

Errors

import { MidlyrAPIError, MidlyrNetworkError } from "@midlyr/sdk-js";

try {
  await midlyr.regulations.get("missing");
} catch (error) {
  if (error instanceof MidlyrAPIError) {
    console.error(error.status, error.code, error.message);
  }

  if (error instanceof MidlyrNetworkError) {
    console.error(error.isTimeout ? "Timed out" : "Network failure");
  }
}

Current scope

@midlyr/sdk-js wraps the current regulation, compliance analysis, and job REST endpoints.

The public SDK surface includes:

• regulations.list() for browsing regulation metadata;
• regulations.get() for document details;
• regulations.getContent() for document text ranges, returned as { regulation, content };
• regulations.query() for vector-search retrieval;
• analysis.screen() for starting screen-analysis jobs;
• jobs.list() and jobs.get() for job history and status.

Out of scope for this package pass:

• MCP tool implementations;
• CLI command behavior;
• job polling helpers;
• a separate resilience package;
• a runtime dependency on ky or another HTTP client.