> ## Documentation Index
> Fetch the complete documentation index at: https://docs.penelope.health/llms.txt
> Use this file to discover all available pages before exploring further.

# Notable Input Types

### State Codes Reference

Full list of valid US state codes for the `states` field in line-of-business responses:

**Standard States** (2-letter codes):
AL, AK, AZ, AR, CA, CO, CT, DE, FL, GA, HI, ID, IL, IN, IA, KS, KY, LA, ME, MD, MA, MI, MN, MS, MO, MT, NE, NV, NH, NJ, NM, NY, NC, ND, OH, OK, OR, PA, RI, SC, SD, TN, TX, UT, VT, VA, WA, WV, WI, WY

**District & Territories**:
DC, PR, GU, VI, AS, CNMI

**Medicare Contractor Subdivisions**:

* NF (Northern California)
* SF (Southern California)
* DN (Downstate New York)
* QN (Queens, New York)
* UN (Upstate New York)
* EM (Eastern Missouri)
* WM (Western Missouri)

### Line of Business Reference

| Line of Business     | Description                          | Coverage                                        |
| -------------------- | ------------------------------------ | ----------------------------------------------- |
| `commercial`         | Private employer-sponsored insurance | Employer groups, individuals                    |
| `medicare_part_a`    | Medicare hospital insurance          | Inpatient hospital, skilled nursing, hospice    |
| `medicare_part_b`    | Medicare medical insurance           | Outpatient, physician services, preventive care |
| `medicare_advantage` | Medicare managed care (Part C)       | Combined A+B benefits through private insurers  |
| `medicaid`           | State-federal public insurance       | Low-income individuals and families             |
| `individual_aca`     | ACA marketplace plans                | Individual and small group coverage             |

### Medical Code System Reference

| System         | Description                         | Format                             | Example          |
| -------------- | ----------------------------------- | ---------------------------------- | ---------------- |
| CPT            | Current Procedural Terminology      | 5-digit numeric or 4-digit + F/T/U | `19318`, `0001F` |
| HCPCS Level 1  | Same as CPT                         | Same as CPT                        | `99213`          |
| HCPCS Level 2  | Non-physician services and supplies | 1 letter + 4 digits                | `J1234`, `A0425` |
| CPT Modifier   | Procedure modifiers                 | 2-character                        | `50`, `59`, `LT` |
| HCPCS Modifier | Service modifiers                   | 2-character                        | `HW`, `F1`       |
| ICD-10-CM      | Diagnosis codes                     | Alphanumeric, 3-7 characters       | `E11.9`, `N62`   |
| ICD-10-PCS     | Procedure codes (inpatient)         | 7-character alphanumeric           | `DB26HZZ`        |

### Date & Retirement Filters

The policy filter provides two complementary date filters:

#### `effective_date` — date range overlap

Returns policies in effect during a given window — those whose effective period overlaps it.

Uses an `EffectiveDateFilter` object:

| Field   | Type   | Description                                                                |
| ------- | ------ | -------------------------------------------------------------------------- |
| `start` | `date` | Window start (inclusive) — policies in effect on or after this date.       |
| `end`   | `date` | Window end (inclusive) — policies that take effect on or before this date. |

#### `retired` — active vs. retired

| Value   | Description                                                   |
| ------- | ------------------------------------------------------------- |
| `false` | Active policies only (no end date, or end date in the future) |
| `true`  | Retired policies only (end date in the past)                  |
| omitted | All policies (no filtering)                                   |

**Common patterns:**

| Goal                                  | Filter                                                           |
| ------------------------------------- | ---------------------------------------------------------------- |
| Currently active policies             | `"retired": false`                                               |
| Retired (superseded) policies         | `"retired": true`                                                |
| Policies effective on a specific date | `"effective_date": {"start": "2025-06-15", "end": "2025-06-15"}` |
| Policies effective after a date       | `"effective_date": {"start": "2025-01-01"}`                      |
| Policies effective before a date      | `"effective_date": {"end": "2025-01-01"}`                        |

Note: `effective_to_date` being null in responses means the policy is currently active; non-null means it was either retired or superseded on that date.