API reference

Eight endpoints over HTTPS, JSON in and out. Every endpoint has its own page with parameters, examples in curl, JavaScript and Python, and real responses.

.mdView as Markdown Open in PlaygroundUpdated 2026-10-30

Base URL and key

base URL

https://api.inplan.io

Send Authorization: Bearer <your key> on every request except /v1/status. See Authentication.

Endpoints

Endpoints
METHOD	PATH	PLAN
GET	`/v1/providers/{npi}`	Free and above
GET	`/v1/providers/{npi}/plans`	Free and above
GET	`/v1/check`	Free and above
POST	`/v1/check/batch`	Builder and above
GET	`/v1/plans/{plan_id}`	Free and above
GET	`/v1/plans/{plan_id}/providers`	Growth and above
GET	`/v1/coverage`	Free and above
GET	`/v1/status`	No key needed

The response envelope

Every successful response has the same top level. Errors use the problem format.

200 OK · envelope, data shortened

{  "request_id": "req_ws7hhhC7uSWYqEye",  "data_as_of": "2026-07-27",  "data": {    "answer": "listed"  },  "sources": [    {      "type": "insurer_directory",      "description": "Provider network directories published by health insurers",      "as_of": "2026-10-29"    },    {      "type": "plan_catalog",      "description": "Published health plan catalogs",      "as_of": "2026-10-28"    }  ],  "notes": [    "in_network=null means no listing was found in current directory data. It is not a statement that the provider is out of network.",    "Network directories change. Confirm with the plan or the provider before care."  ]}

Envelope fields
FIELD	DESCRIPTION
`request_id` string	Unique to this request. Also sent as the `X-Request-Id` header. Quote it when you contact support.
`data_as_of` date \| null	The date of the newest data behind this response.
`data` object	The answer. Its fields depend on the endpoint and are listed below.
`sources` object[]	The types of data behind the response, each with its date.
`sources[].type` string	The source type: `insurer_directory`, `plan_directory`, `provider_registry` or `plan_catalog`.
`sources[].description` string	The source type in plain words.
`sources[].as_of` date \| null	The date this type of data is current to.
`notes` string[]	Short notes to show next to the answer. Present on most endpoints.

Files for tools and agents

/openapi.json: OpenAPI 3.1, with real response examples.
Postman collection: import it, then set INPLAN_KEY in the collection variables.
/llms.txt and /llms-full.txt: these docs for language models.

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