Client

What the client does itself, beside its surfaces: batched reads and the one-call account snapshot. Constructor options are in the SDK guide.

@secondlayer/sdk@15.5.02 methodsfrom source with openpkgSDK guide Instance API

new SecondLayer(options)
batch(requests)	{ results: { path: string \| null; s…	Run up to 10 public reads in one round trip (`POST /v1/batch`).
context()	ContextSnapshot	Get a one-call snapshot of your account and instance.

new SecondLayer(options)

source

new SecondLayer(

options?: {

baseUrl?: string;

apiKey?: string;

accountKey?: string;

fetchImpl?: FetchLike;

dumpsBaseUrl?: string;

archiveBaseUrl?: string;

archiveOpsUrl?: string;

origin?: "cli" | "mcp" | "session";

verify?: boolean | { publicKey: string; };

verifyDumpsManifest?: boolean;

requestTimeoutMs?: number;

etagCache?: false | EtagCache;

)

Parameters

hover a row to find it in the code

Options

`baseUrl`string	Base URL of the instance API (trailing slashes are stripped).
`apiKey`string	Bearer token for authenticated requests. Defaults to `SECONDLAYER_API_KEY` on `api.secondlayer.tools`, `INSTANCE_TOKEN` elsewhere.
`accountKey`string	Hosted account key (`sk-sl_*`). Env `SECONDLAYER_API_KEY`. Used by `sl.archive` quote/fetch/credits; reaches `/v1` and `/api` only through `apiKey` when the base URL is the hosted API.
`fetchImpl`FetchLike	Fetch implementation. Tests and edge runtimes can provide their own.
`dumpsBaseUrl`string	Public base URL for Streams bulk parquet dumps (the cold backfill plane). Required for `streams.dumps.*`; without it the dumps client falls back to its built-in default.
`archiveBaseUrl`string	Public base URL for the signed canonical archive tree. Defaults to `https://archive.secondlayer.tools`. Reaches `sl.archive`.
`archiveOpsUrl`string	Credits and fetch-gate API. Defaults to `https://api.secondlayer.tools`, not `baseUrl`. Reaches `sl.archive` quote/fetch/credits.
`origin`"cli" \| "mcp" \| "session"	Deploy origin label sent as `x-sl-origin` (telemetry). Defaults to `cli`.

4 more options

`verify`boolean \| { publicKey: string; }	Check the ed25519 signature on every Streams read. Omit for lenient (verify when signed, pass through unsigned self-host responses), `true` or `{ publicKey }` for strict, `false` for off. Reaches `sl.streams`.
`verifyDumpsManifest`boolean	Check the dumps manifest signature before trusting any file hash (default on). Reaches `sl.streams.dumps`.
`requestTimeoutMs`number	How long one request may take, headers and body, before it fails with a retryable `ApiError` (default 30 000 ms). A hung socket then trips the retry policy instead of stalling a walk or consume loop forever. `0` disables the timeout.
`etagCache`false \| EtagCache	Where GET responses carrying an `ETag` are kept, so a repeat read sends `If-None-Match` and a finalized page comes back as a free `304`. Defaults to an in-memory store of the last 64 pages. Pass your own to keep it across processes (a file, a KV), or `false` to turn it off.

sl.batch(requests)

REST POST /v1/batch source

Run up to 10 public reads in one round trip (POST /v1/batch).

Each item is authorized on its own; the client's bearer token applies to every item. Results come back in order as { path, status, body }. Only paths under /v1/index/, /v1/subgraphs, /v1/streams/, and /v1/contracts are allowed; anything else is a per-item 400.

sl.batch(

requests: { path: string; params?: Record<string, string | number | boolean> }[],

): Promise<{ results: { path: string | null; status: number; body: unknown }[] }>

import { SecondLayer } from "@secondlayer/sdk";

const sl = new SecondLayer({

apiKey: process.env.SECONDLAYER_API_KEY,

});

const { results } = await sl.batch([

{ path: "/v1/streams/tip" },

{ path: "/v1/index/pox5/events", params: { topic: "stake", limit: 5 } },

]);

for (const result of results) {

console.log(result.path, result.status);

^Each item has its own status, so one failed read does not fail the batch.

}

Parameters

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Required

requestsrequired{ path: string; params?: Record<string, string | number…

sl.context()

REST GET /api/accounts/mesource

Get a one-call snapshot of your account and instance.

Returns a ContextSnapshot: the same orientation an MCP agent reads from secondlayer://context, available to any SDK or CLI consumer. Reads run concurrently; a failed read lands as { value: null, error } on its field rather than rejecting the whole snapshot.

sl.context(): Promise<ContextSnapshot>

Returns Promise<ContextSnapshot>

account: ContextField<ContextAccount>
streamsTip: ContextField<StreamsTip>
indexTip: ContextField<IndexTip>
subgraphs: ContextField<SubgraphSummary[]>
webhooks: ContextField<{ count: number; byStatus: Record<string, number> }>
activeOperations: ContextField<ActiveSubgraphOperation[]>
instance: ContextField<InstanceDiagnosis>

Types on this page

ActiveSubgraphOperation

subgraph, operationId, kind, status, progress

ContextAccount

email

ContextField

One snapshot field: the value, or null plus the error that produced it.

ContextFieldError

Why one snapshot field could not be read.

ContextSnapshot

A point-in-time orientation snapshot: live tips and what this instance holds.

EtagCache

Storage for etagCache.

EtagEntry

One cached GET response: its validator and the body it validated.

FetchLike

(input: string | URL | Request, init?: RequestInit) => Promise<Response>

IndexTip

block_height, finalized_height, lag_seconds

InstanceDiagnosis

An instance's state, the API verdict, and the issues found.

InstanceIssue

title, detail, nextSteps

InstanceState

"healthy" | "empty-index" | "degraded"

StreamsTip

The chain tip: latest block, Bitcoin anchor, and finality boundary.

SubgraphSummary

A subgraph's name, status, and indexing progress.

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