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

# Response Fields

> Which fields a section carries, which corpus each one belongs to, and how to tell 'not applicable' from 'we do not have it'

A section object is one shape across every corpus, so a result always carries the
same keys whatever you searched.
Most of them will be `null`, because most belong to a different corpus.

A Federal Register rule has a docket number and a comment-close date.
A US Code section has a source credit and a chapter.
A court rule has a rule set.
None of those apply to the others, and a null there means the field does not
apply, not that we are missing it.

This page tells the two apart.

## The rule

<Note>
  A `null` on a field this page marks as **not applicable** for your `corpusType`
  carries no information. A `null` on a field marked **expected** is a real gap,
  and worth telling us about.
</Note>

## Always present

These carry a value on every section in every corpus.

| Field           | Meaning                                                                                                        |
| --------------- | -------------------------------------------------------------------------------------------------------------- |
| `actId`         | The stable identifier. Use it for every follow-up call.                                                        |
| `citation`      | The full citation, including the edition year where the publisher prints one.                                  |
| `citationShort` | The citation without the edition year.                                                                         |
| `title`         | The section's own heading.                                                                                     |
| `corpusType`    | Which body of law this came from.                                                                              |
| `state`         | `federal`, or the two-letter jurisdiction.                                                                     |
| `actStatus`     | `in_force`, `repealed`, `superseded`, `reserved` and similar.                                                  |
| `goodLawStatus` | Our verdict on whether it is still good law. See [Status & Currency](/docs/api-guide/concepts/status-and-currency). |
| `externalUrl`   | The publisher's own page for this section.                                                                     |

## By corpus type

`o` = expected to carry a value. `-` = not applicable, ignore the null.

| Field                                   | USC | CFR | STATE | FEDERAL\_REGISTER | EXECUTIVE\_ACTION |
| --------------------------------------- | :-: | :-: | :---: | :---------------: | :---------------: |
| `titleNumber` / `titleName`             |  o  |  o  |   o   |         -         |         -         |
| `chapter` / `chapterName`               |  o  |  -  |   o   |         -         |         -         |
| `subchapter` / `subchapterName`         |  o  |  -  |   o   |         -         |         -         |
| `part` / `partName`                     |  -  |  o  |   -   |         -         |         -         |
| `subpart` / `subpartName`               |  -  |  o  |   -   |         -         |         -         |
| `sourceCredit`                          |  o  |  -  |   -   |         -         |         -         |
| `publicLawCites`                        |  o  |  -  |   -   |         -         |         -         |
| `currentThrough`                        |  o  |  -  |   -   |         -         |         -         |
| `amendmentYears` / `lastAmendedYear`    |  o  |  o  |   o   |  o (final rules)  |         o         |
| `effectiveDate`                         |  o  |  -  |   o   |  o (final rules)  |         o         |
| `statutoryAuthority`                    |  -  |  o  |   o   |         -         |         -         |
| `frDocketIds` / `frRegulationIdNumbers` |  -  |  -  |   -   |         o         |         -         |
| `frEffectiveOn` / `frCommentsCloseOn`   |  -  |  -  |   -   |         o         |         -         |
| `frVolume` / `frStartPage`              |  -  |  -  |   -   |         o         |         -         |
| `president` / `signingDate`             |  -  |  -  |   -   |         -         |         o         |
| `documentNumber`                        |  -  |  -  |   -   |         o         |         o         |
| `ruleSet` / `ruleSetCode`               |  -  |  -  |   -   |         -         |         -         |
| `articleNumber` / `articleName`         |  -  |  -  |   -   |         -         |         -         |

`ruleSet` belongs to `STATE_RULES` and `FEDERAL_RULES`; `articleNumber` to
`CONSTITUTION` and `STATE_CONSTITUTION`.

## Fields that are reserved and not yet populated

We publish these keys so the shape does not change under you when they start
carrying values. Today they are null everywhere.

| Field                         | Intended meaning                                          |
| ----------------------------- | --------------------------------------------------------- |
| `supersededBy` / `supersedes` | Links between a section and the version that replaced it. |
| `priorEffectiveDates`         | Earlier effective dates for the same section.             |
| `versionId`                   | An identifier for one version of a section.               |

<Warning>
  We do not currently serve prior versions of a section, for any corpus.
  A section object is the current text as of `currentThrough` or the edition in
  its `citation`, and there is no endpoint that returns what it said previously.
  If point-in-time matters to your use case, tell us: it changes what we build
  next.
</Warning>

## Amendment fields on the Federal Register

`amendmentYears` on a **final rule** is the year that rule was published, which
is the year it amended the CFR.
A **proposed rule** carries no amendment years at all, because it amended
nothing.

That asymmetry is deliberate.
A proposed rule that was never finalized, or was withdrawn, must not look like
enacted law on the field a currency query trusts.

## Filtering by year

`yearFrom` and `yearTo` range over `lastAmendedYear` and `effectiveYear`.

<Note>
  A corpus whose sections carry neither is not reachable by a year filter at all,
  and will return zero results rather than an error.
  Check the table above before filtering: for proposed rules in particular, a year
  window returns nothing by design.
</Note>

## Related

* [Corpus Types](/docs/api-guide/concepts/corpus-types) for what each corpus contains.
* [Amendment History](/docs/api-guide/concepts/amendment-history) for where the years come from.
* [Status & Currency](/docs/api-guide/concepts/status-and-currency) for `actStatus` and `goodLawStatus`.