Authenticate querying.ai API requests with an API key

Send your API key in the Authorization header of every request:

curl https://api.querying.ai/v1/async/task/8f2c1e40-... \
  -H "Authorization: Bearer $QUERYING_API_KEY"

Keys start with vt_. A key works as soon as you create it.

Get a key

Sign up at querying.ai. New accounts start with 500 free credits.
Open API keys in the dashboard and create a key.
Copy the key when it is shown. Store it in an environment variable or a secrets manager.

An account can hold up to 5 active keys. Keep a slot available for a planned replacement, then keep both keys active while switching clients:

Create an additional key in the dashboard with the required engine scope, daily credit limit and expiry.
Update all callers and webhook signature verification to use the new key. Verify that requests succeed; retain the old signing key for deliveries from tasks submitted with it.
Wait for batches created with the old key to finish, then revoke that key.

Dashboard rotation issues a new key with the same settings and revokes the old key immediately. Requests using the old key then return 401; clients must switch to the new key to resume.

Use the key only from server-side code. Anyone holding the key can spend your credits. Do not ship it in a browser app, a mobile app, or a public repository.

Key settings

Each key has optional settings you set in the dashboard:

Setting	Effect
Engine scope	The key can submit only the listed `taskType` values. Any other engine returns `403 KEY_SCOPE_DENIED`. An empty scope allows every engine.
Daily credit limit	The most credits the key can spend per UTC day, from 0.01 to 20,000,000. A task that would exceed it returns `429 KEY_DAILY_CREDIT_LIMIT`; `details.retryAfterSec` counts down to the next UTC midnight.
Expiry	The key stops working at this time, set between 5 minutes and 2 years ahead.

See Credits and limits for account-wide limits.

Which endpoints need a key

Endpoints	Key
`GET /health`, `GET /ready`, `GET /health/*`	Not needed
`GET /v1/capabilities` (engines, prices, country rules)	Not needed
`GET /v1/evidence/{file}` (answer evidence files; the file name is the access token)	Not needed
Everything else: tasks, batches, grids, Citation Analysis, Prompt Research, Product Lookup, monitors, exports, sub-accounts, `/stats`, `/capacity`	Required

Errors

A missing, malformed, revoked or expired key returns 401. On task, batch and research endpoints the code is MISSING_API_KEY:

{
  "success": false,
  "error": {
    "code": "MISSING_API_KEY",
    "message": "Missing or invalid API key",
    "timestamp": "2026-10-19T04:12:00.000Z"
  }
}

Status	Code	Meaning
`401`	`MISSING_API_KEY`	No key, or the key is invalid, revoked or expired.
`401`	`UNAUTHORIZED`	The same, on monitor and export endpoints.
`403`	`KEY_SCOPE_DENIED`	The key’s engine scope does not include this `taskType`.
`403`	`ENGINE_PRIVATE`	The engine is not available on self-serve plans.
`429`	`KEY_DAILY_CREDIT_LIMIT`	The key reached its daily credit limit.
`503`	`DB_UNAVAILABLE`	The key could not be checked. Retry after `Retry-After`; the key was neither accepted nor rejected.

In a batch created with POST /v1/batches, items not yet started are rejected with API_KEY_INACTIVE if the batch’s key is revoked or expires while the batch runs. Full error reference: Errors.

Get started

Core concepts

Answer engines

Search and web data

Request options

Research

GEO monitoring

Account and data

Authenticate querying.ai API requests with an API key

Get a key

Key settings

Which endpoints need a key

Errors

​Get a key

​Key settings

​Which endpoints need a key

​Errors

Get a key

Key settings

Which endpoints need a key

Errors