API overview

The client libraries (TypeScript, Python, Rust) wrap this API: typed queries, pagination, retries, and Arrow decoded into JSON rows.

Base URLs

Each chain has a base URL. Every endpoint below is relative to it.

Chain	Base URL	Alternative
Ethereum	`https://api.bloklake.com/v1/chains/eth`	`https://eth.api.bloklake.com`
Robinhood Chain	`https://api.bloklake.com/v1/chains/rh`	`https://rh.api.bloklake.com`

Method and path	Purpose	Key	Billed
`POST /query`	Run a query, get Arrow IPC streams	yes	yes
`POST /query/json`	Run a query, get JSON	yes	yes
`POST /v1/sets`	Create (or find) a set of addresses or topics	yes	10 KB
`GET /v1/sets/{id}`	A set’s metadata	yes	10 KB
`DELETE /v1/sets/{id}`	Delete a set	yes	10 KB
`POST /v1/queries`	Register a prepared query	yes	10 KB
`GET /status`	Chain head, finalized block, block range	no	free
`GET /v1/schema`	Every field and whether this chain has it	no	free
`GET /v1/account`	Your key’s plan, limits and balance	yes	free
`GET /healthz`	Liveness: `200 ok`	no	free

Send your API key in the Authorization header:

Authorization: Bearer bl_live_xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx

x-api-key and X-BL-Api-Key headers are accepted too. Keys are created in the dashboard; see API keys.

Request bodies are JSON (content-type: application/json), up to 8 MiB (about 5.5 MiB for POST /v1/sets).
Unknown keys anywhere in a body are rejected with 400, never ignored.
Hex values are 0x-prefixed and case-insensitive.
HTTP/1.1 and HTTP/2 are supported. Responses are not compressed.
The API sends no CORS headers: call it from servers, not browsers.

POST /query: application/vnd.apache.arrow.stream. See Reading Arrow.
Everything else: application/json.
Errors: a non-200 status and {"error": {"code": "…", "message": "…"}}. See Errors.

Header	Meaning
`X-Request-Id`	your `X-Request-Id` (up to 128 printable characters) or a generated one; quote it to support
`X-RateLimit-Limit`	your key’s requests per second (admitted requests)
`X-RateLimit-Remaining`	requests left in the current second
`Retry-After`	on `429` and `503`: seconds to wait