# Answers and evidence

Every check answers one question: does the plan's network directory list this provider? The answer is `listed` with evidence, or `not_found`. We never turn a missing listing into a "no".

Source: https://inplan.io/docs/answers-and-evidence · Updated 2026-10-30

## The answer values

| Answer | In_network | Meaning |
| --- | --- | --- |
| `listed` | `true` | The network directory of this plan lists the provider. `evidence` holds each listing. |
| `not_found` | `null` | No listing found in current directory data for this provider and plan. It is not a statement that the provider is out of network. |
| `no_provider_network` | `null` | The plan id is a prescription drug plan (it starts with S). Drug plans have no provider network. |

`in_network: false` is kept for an explicit exclusion that an insurer publishes. v1 does not return it today. Handle it anyway: treat `false` as "the plan says this provider is not in its network".

## How to show it

- **LISTED · in_network: true**: Say "Listed" or "In this plan's directory". Show the plan year and the date from `evidence[].source.as_of`.
- **NOT FOUND · in_network: null**: Say "Not found" or "We could not find a listing". Ask the user to confirm with the plan or the provider. Never show it as "out of network".

`data.explanation` is one plain sentence for the answer. You can show it as it is. `notes` holds short sentences to show next to the answer, for example that directories change and that users should confirm before care.

## The evidence block

`data.evidence[]` holds one entry for each listing we found, newest plan year first. It is empty when the answer is `not_found`. Each entry carries its own source: the source type and the date we read it.

| Field | Description |
| --- | --- |
| `plan_id` / `plan_year` | The plan and the plan year of this listing. |
| `network_tier` | Marketplace plans: the tier the directory names, for example `PARTICIPATING` or `PREFERRED`. |
| `accepting_new_patients` | Medicare Advantage plans: whether the directory says the provider accepts new patients. |
| `provider_kind` | Medicare Advantage plans: the kind of provider listed, for example `practitioner`. |
| `source.type` | `insurer_directory` for marketplace plans, `plan_directory` for Medicare Advantage plans. |
| `source.as_of` | The date we read that directory. |

A Medicare Advantage answer carries `accepting_new_patients` and `provider_kind` instead of a tier:

Response (200 OK · Medicare Advantage, listed):

```json
{
  "data": {
    "npi": "1184617268",
    "plan_id": "H2526-001-000",
    "input_plan_id": "H2526-001-000",
    "market": "ma",
    "plan_years_listed": [
      2027
    ],
    "in_network": true,
    "answer": "listed",
    "explanation": "The plan's network directory lists this provider for this plan.",
    "evidence": [
      {
        "plan_id": "H2526-001-000",
        "plan_year": 2027,
        "accepting_new_patients": true,
        "provider_kind": "practitioner",
        "source": {
          "type": "plan_directory",
          "as_of": "2026-10-29"
        }
      }
    ],
    "plan_year": 2027,
    "plan": {
      "plan_name": "DEVOTED CHOICE 001 OH (PPO)",
      "organization": "Devoted Health",
      "plan_type": "PPO",
      "service_area_states": [
        "OH"
      ]
    },
    "source": {
      "type": "plan_directory",
      "as_of": "2026-10-29"
    },
    "as_of": "2026-10-29"
  }
}
```

## A not_found answer

A `not_found` answer still returns the plan details we hold, so you can show which plan was checked. `evidence` is empty and `plan_years_listed` is `[]`.

Response (200 OK · not_found):

```json
{
  "data": {
    "npi": "1376006148",
    "plan_id": "13262AR0230002",
    "input_plan_id": "13262AR0230002",
    "market": "aca",
    "plan_years_listed": [],
    "in_network": null,
    "answer": "not_found",
    "explanation": "No listing found in current directory data for this provider and plan.",
    "evidence": [],
    "plan_year": 2026,
    "plan": {
      "plan_name": "HA Silver AH",
      "issuer": {
        "id": "13262",
        "name": "Health Advantage"
      },
      "state": "AR",
      "metal_level": "Silver",
      "plan_type": "POS",
      "variant": null
    },
    "source": {
      "type": "insurer_directory",
      "as_of": "2026-10-28"
    },
    "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."
  ]
}
```

## Source types

We name sources by type. The `sources` array of every response lists the types behind it, each with the date it is current to.

| Type | What it is |
| --- | --- |
| `insurer_directory` | Provider network directories published by health insurers (marketplace plans). |
| `plan_directory` | Provider network directories published by Medicare Advantage plans. |
| `provider_registry` | National provider registry and practice records: names, credentials, specialties, locations. |
| `plan_catalog` | Published health plan catalogs: plan names, insurers, metal levels, plan types. |