---
url: >-
  https://adk.nht.io/api/@nhtio/adk/batteries/artifacts/yaml/classes/SpooledYamlArtifact.md
description: 'A [`SpooledArtifact`](https://adk.nht.io/api/@nhtio/adk/spooled_artifact/classes/SpooledArtifact) specialisation that adds YAML-aware read operations.'
---

# Class: SpooledYamlArtifact

Defined in: [src/batteries/artifacts/yaml/index.ts:95](https://github.com/NHTIO/ADK/blob/v1.20260907.0/src/src/batteries/artifacts/yaml/index.ts#L95)

A [SpooledArtifact](../../../../spooled_artifact/classes/SpooledArtifact.md) specialisation that adds YAML-aware read operations.

## Remarks

Handles both single-document YAML and multi-document streams (delimited by `---`).
Parsed documents are cached in a private field for the lifetime of the instance.

For multi-document streams:

* `yaml_length` reports the document count.
* `yaml_keys` returns the deduplicated union of keys across all documents.
* `yaml_get` / `yaml_filter` / `yaml_pluck` evaluate paths against all documents and return
  a flat array of all matches.

Non-finite numbers (`.NaN`, `.inf`, `-.inf`) present in the YAML are preserved through the
`yaml_to_json` converter using a custom replacer.

## Extends

* [`SpooledArtifact`](../../../../spooled_artifact/classes/SpooledArtifact.md)

## Constructors

### Constructor

```ts
new SpooledYamlArtifact(reader: SpoolReader, options?: {
  multiDocument?: boolean;
}): SpooledYamlArtifact;
```

Defined in: [src/batteries/artifacts/yaml/index.ts:108](https://github.com/NHTIO/ADK/blob/v1.20260907.0/src/src/batteries/artifacts/yaml/index.ts#L108)

#### Parameters

| Parameter                | Type                                                                    | Description                                                                                                                                                                                                                                                                                                                                                                                               |
| ------------------------ | ----------------------------------------------------------------------- | --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| `reader`                 | [`SpoolReader`](../../../../spooled_artifact/interfaces/SpoolReader.md) | The backing store to read from.                                                                                                                                                                                                                                                                                                                                                                           |
| `options?`               | { `multiDocument?`: `boolean`; }                                      | Optional configuration for parsing.                                                                                                                                                                                                                                                                                                                                                                       |
| `options.multiDocument?` | `boolean`                                                               | Declares the source's document mode. `true` parses as a stream and makes [SpooledYamlArtifact.yaml\_type](#yaml_type) report `'multi-document'` regardless of the current count. `false` asserts exactly one document and parses with `load`, so a `---` stream raises `E_YAML_PARSE_ERROR` instead of being silently accepted. When omitted, mode is auto-detected by parsing the content with `loadAll`. |

#### Returns

`SpooledYamlArtifact`

#### Overrides

[`SpooledArtifact`](../../../../spooled_artifact/classes/SpooledArtifact.md).[`constructor`](../../../../spooled_artifact/classes/SpooledArtifact.md#constructor)

## Properties

| Property                                        | Modifier | Type                                                                                       | Description                                                                                                                                                                                                                                                                                                                                                                                                                   | Overrides                                                                                                                                                                  | Defined in                                                                                                                                  |
| ----------------------------------------------- | -------- | ------------------------------------------------------------------------------------------ | ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | -------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | ------------------------------------------------------------------------------------------------------------------------------------------- |
|  `toolMethods` | `static` | readonly [`ToolMethodDescriptor`](../../../../common/interfaces/ToolMethodDescriptor.md)\[] | The YAML-specific artifact-query descriptors this class adds on top of the base set. **Remarks** Lists `artifact_yaml_type`, `artifact_yaml_keys`, `artifact_yaml_length`, `artifact_yaml_get`, `artifact_yaml_filter`, `artifact_yaml_slice`, `artifact_yaml_pluck`. The base seven descriptors (`artifact_head`, etc.) are NOT included here — they are forged separately by [SpooledYamlArtifact.forgeTools](#forgetools). | [`SpooledArtifact`](../../../../spooled_artifact/classes/SpooledArtifact.md).[`toolMethods`](../../../../spooled_artifact/classes/SpooledArtifact.md#property-toolmethods) | [src/batteries/artifacts/yaml/index.ts:139](https://github.com/NHTIO/ADK/blob/v1.20260907.0/src/src/batteries/artifacts/yaml/index.ts#L139) |

## Methods

### \[ENCODE\_METHOD]\()

```ts
ENCODE_METHOD: unknown;
```

Defined in: [src/batteries/artifacts/yaml/index.ts:455](https://github.com/NHTIO/ADK/blob/v1.20260907.0/src/src/batteries/artifacts/yaml/index.ts#L455)

Serialise this SpooledYamlArtifact into an `@nhtio/encoder` snapshot.

#### Returns

`unknown`

A snapshot consumed by SpooledYamlArtifact.\[DECODE\_METHOD].

#### Remarks

Overrides SpooledArtifact.\[ENCODE\_METHOD] to carry the constructor's `multiDocument`
option. The parsed-document cache is derived and not encoded. Round-trips via
SpooledYamlArtifact.\[DECODE\_METHOD].

#### Inherited from

[`SpooledArtifact`](../../../../spooled_artifact/classes/SpooledArtifact.md).[`[ENCODE_METHOD]`](../../../../spooled_artifact/classes/SpooledArtifact.md#encode_method)

***

### \[ENCODE\_METHOD]\()

```ts
ENCODE_METHOD: unknown;
```

Defined in: [src/lib/classes/spooled\_artifact.ts:314](https://github.com/NHTIO/ADK/blob/v1.20260907.0/src/src/lib/classes/spooled_artifact.ts#L314)

Serialise this SpooledArtifact into an `@nhtio/encoder` snapshot — the reader **handle**, not the
bytes.

#### Returns

`unknown`

A snapshot consumed by SpooledArtifact.\[DECODE\_METHOD].

#### Remarks

Emits the backing reader's [ReaderDescriptor](../../../../common/interfaces/ReaderDescriptor.md); decode re-binds the reader through the
registered resolver. Throws [@nhtio/adk!E\_READER\_NOT\_DESCRIBABLE](../../../../exceptions/variables/E_READER_NOT_DESCRIBABLE.md) when the reader cannot
describe itself. Subclasses override this to include their own discriminators (e.g.
[@nhtio/adk!SpooledJsonArtifact](../../../../spooled_artifact/classes/SpooledJsonArtifact.md) adds `format`).

#### Inherited from

```ts
SpooledArtifact.[ENCODE_METHOD]
```

***

### asString()

```ts
asString(): Promise<string>;
```

Defined in: [src/lib/classes/spooled\_artifact.ts:630](https://github.com/NHTIO/ADK/blob/v1.20260907.0/src/src/lib/classes/spooled_artifact.ts#L630)

Returns the full artifact body as a single byte-faithful string.

#### Returns

`Promise`<`string`>

The full content as a single string.

#### Remarks

Round-trip faithful to whatever bytes the [@nhtio/adk!SpoolReader](../../../../spooled_artifact/interfaces/SpoolReader.md) was constructed over —
preserves trailing newlines and non-`\n` line terminators that [SpooledArtifact.cat](../../../../spooled_artifact/classes/SpooledArtifact.md#cat)
discards via its line-based view. This is the canonical primitive for "inline the artifact
content directly into a message" use cases.

`asString()` and the static `forgeTools(ctx)` factory on each subclass are independent
alternatives — a consumer chooses per turn whether to inline the body in a message
(`await tc.results.asString()`) or hand the model query tools
(`SpooledArtifact.forgeTools(ctx)`). Neither calls the other; either works with neither.

#### Inherited from

[`SpooledArtifact`](../../../../spooled_artifact/classes/SpooledArtifact.md).[`asString`](../../../../spooled_artifact/classes/SpooledArtifact.md#asstring)

***

### byteLength()

```ts
byteLength(): Promise<number>;
```

Defined in: [src/lib/classes/spooled\_artifact.ts:501](https://github.com/NHTIO/ADK/blob/v1.20260907.0/src/src/lib/classes/spooled_artifact.ts#L501)

Returns the total byte length of the underlying data.

#### Returns

`Promise`<`number`>

The byte length as reported by the [@nhtio/adk!SpoolReader](../../../../spooled_artifact/interfaces/SpoolReader.md).

#### Inherited from

[`SpooledArtifact`](../../../../spooled_artifact/classes/SpooledArtifact.md).[`byteLength`](../../../../spooled_artifact/classes/SpooledArtifact.md#bytelength)

***

### cat()

```ts
cat(start?: number, end?: number): Promise<string[]>;
```

Defined in: [src/lib/classes/spooled\_artifact.ts:482](https://github.com/NHTIO/ADK/blob/v1.20260907.0/src/src/lib/classes/spooled_artifact.ts#L482)

Returns lines from the artifact, optionally bounded to a range.

#### Parameters

| Parameter | Type     | Description                                                    |
| --------- | -------- | -------------------------------------------------------------- |
| `start?`  | `number` | 0-based start line index (inclusive). Defaults to `0`.         |
| `end?`    | `number` | 0-based end line index (exclusive). Defaults to `lineCount()`. |

#### Returns

`Promise`<`string`\[]>

Array of line strings in the requested range.

#### Remarks

Without arguments, returns all lines — equivalent to POSIX `cat`. With `start` and/or `end`,
behaves like `Array.prototype.slice`: `start` defaults to `0`, `end` defaults to the total
line count, and only lines in `[start, end)` are fetched from the backing store. For large
artifacts, prefer a bounded range or [SpooledArtifact.head](../../../../spooled_artifact/classes/SpooledArtifact.md#head) / [SpooledArtifact.tail](../../../../spooled_artifact/classes/SpooledArtifact.md#tail).

#### Inherited from

[`SpooledArtifact`](../../../../spooled_artifact/classes/SpooledArtifact.md).[`cat`](../../../../spooled_artifact/classes/SpooledArtifact.md#cat)

***

### estimateHandleTokens()

```ts
estimateHandleTokens(
   callId: string,
   encoding:
  | "gpt2"
  | "r50k_base"
  | "p50k_base"
  | "p50k_edit"
  | "cl100k_base"
  | "o200k_base"
  | "gemini"
  | "gemma"
  | "llama2"
  | "claude",
   renderer?: (input: {
  artifact: unknown;
  byteLength: number;
  callId: string;
  encoding?: string;
  estimatedTokens?: number;
  lineCount: number;
}) => string): number;
```

Defined in: [src/lib/classes/spooled\_artifact.ts:547](https://github.com/NHTIO/ADK/blob/v1.20260907.0/src/src/lib/classes/spooled_artifact.ts#L547)

Estimates tokens for the exact handle-body metadata rendered for this artifact.

The fallback renderer is an interim core-safe implementation. Its output is deliberately
specified here for fan-in parity: the lines are the fixed prose and metadata strings below,
with one `\n` separator, and method entries formatted as `- name — description` (or `- name`).
The canonical renderer in `chat_common` should eventually delegate to this builder rather than
maintain a second copy.

#### Parameters

| Parameter   | Type                                                                                                                                                                        | Description                                       |
| ----------- | --------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | ------------------------------------------------- |
| `callId`    | `string`                                                                                                                                                                    | The turn-local artifact identifier.               |
| `encoding`  | | `"gpt2"` | `"r50k_base"` | `"p50k_base"` | `"p50k_edit"` | `"cl100k_base"` | `"o200k_base"` | `"gemini"` | `"gemma"` | `"llama2"` | `"claude"`                  | The token encoding used for estimation.           |
| `renderer?` | (`input`: { `artifact`: `unknown`; `byteLength`: `number`; `callId`: `string`; `encoding?`: `string`; `estimatedTokens?`: `number`; `lineCount`: `number`; }) => `string` | Optional renderer overriding the interim default. |

#### Returns

`number`

A synchronous token estimate.

#### Inherited from

[`SpooledArtifact`](../../../../spooled_artifact/classes/SpooledArtifact.md).[`estimateHandleTokens`](../../../../spooled_artifact/classes/SpooledArtifact.md#estimatehandletokens)

***

### estimateTokens()

```ts
estimateTokens(encoding:
  | "gpt2"
  | "r50k_base"
  | "p50k_base"
  | "p50k_edit"
  | "cl100k_base"
  | "o200k_base"
  | "gemini"
  | "gemma"
  | "llama2"
| "claude"): Promise<number>;
```

Defined in: [src/lib/classes/spooled\_artifact.ts:609](https://github.com/NHTIO/ADK/blob/v1.20260907.0/src/src/lib/classes/spooled_artifact.ts#L609)

Estimates the total token count of the artifact under `encoding`.

#### Parameters

| Parameter  | Type                                                                                                                                                       | Description                                  |
| ---------- | ---------------------------------------------------------------------------------------------------------------------------------------------------------- | -------------------------------------------- |
| `encoding` | | `"gpt2"` | `"r50k_base"` | `"p50k_base"` | `"p50k_edit"` | `"cl100k_base"` | `"o200k_base"` | `"gemini"` | `"gemma"` | `"llama2"` | `"claude"` | The encoding identifier to use for counting. |

#### Returns

`Promise`<`number`>

The estimated number of tokens.

#### Remarks

Reads the full byte-faithful content via [SpooledArtifact.asString](../../../../spooled_artifact/classes/SpooledArtifact.md#asstring) (which delegates to
[@nhtio/adk!SpoolReader.readAll](../../../../spooled_artifact/interfaces/SpoolReader.md#readall)) and delegates to [@nhtio/adk!Tokenizable.estimateTokens](../../../../common/classes/Tokenizable.md#estimatetokens). The estimate
therefore reflects the actual source bytes — including trailing newlines and non-`\n` line
terminators that the line-based [SpooledArtifact.cat](../../../../spooled_artifact/classes/SpooledArtifact.md#cat) view would otherwise discard or
misrepresent.

#### Inherited from

[`SpooledArtifact`](../../../../spooled_artifact/classes/SpooledArtifact.md).[`estimateTokens`](../../../../spooled_artifact/classes/SpooledArtifact.md#estimatetokens)

***

### grep()

```ts
grep(pattern: RegExp): Promise<string[]>;
```

Defined in: [src/lib/classes/spooled\_artifact.ts:454](https://github.com/NHTIO/ADK/blob/v1.20260907.0/src/src/lib/classes/spooled_artifact.ts#L454)

Returns all lines that match `pattern`.

#### Parameters

| Parameter | Type     | Description                                       |
| --------- | -------- | ------------------------------------------------- |
| `pattern` | `RegExp` | The regular expression to test each line against. |

#### Returns

`Promise`<`string`\[]>

Array of matching line strings, in order.

#### Remarks

Behaves like POSIX `grep`: each line is tested against the pattern and included in the result
when it matches. The pattern is applied as a JavaScript `RegExp`; flags (e.g. case-
insensitivity) should be encoded in the expression itself.

Stateful flags (`g`, `y`) on the supplied `RegExp` would normally cause `pattern.test()` to
advance `lastIndex` across calls, producing skipped matches and order-dependent results. To
keep the per-line semantics stateless, `grep` resets `pattern.lastIndex` to `0` before each
line test. The forged `artifact_grep` tool also rejects `g` and `y` flags up-front at schema
validation time.

#### Inherited from

[`SpooledArtifact`](../../../../spooled_artifact/classes/SpooledArtifact.md).[`grep`](../../../../spooled_artifact/classes/SpooledArtifact.md#grep)

***

### hasSizeHints()

```ts
hasSizeHints(): boolean;
```

Defined in: [src/lib/classes/spooled\_artifact.ts:520](https://github.com/NHTIO/ADK/blob/v1.20260907.0/src/src/lib/classes/spooled_artifact.ts#L520)

Returns whether producer-computed size metadata is available.

#### Returns

`boolean`

`true` when SpooledArtifact.\_setSizeHints has populated the cache.

#### Inherited from

[`SpooledArtifact`](../../../../spooled_artifact/classes/SpooledArtifact.md).[`hasSizeHints`](../../../../spooled_artifact/classes/SpooledArtifact.md#hassizehints)

***

### head()

```ts
head(n?: number): Promise<string[]>;
```

Defined in: [src/lib/classes/spooled\_artifact.ts:401](https://github.com/NHTIO/ADK/blob/v1.20260907.0/src/src/lib/classes/spooled_artifact.ts#L401)

Returns the first `n` lines of the artifact.

#### Parameters

| Parameter | Type     | Default value | Description                                |
| --------- | -------- | ------------- | ------------------------------------------ |
| `n`       | `number` | `10`          | Number of lines to return. Defaults to 10. |

#### Returns

`Promise`<`string`\[]>

Array of line strings, without trailing newlines.

#### Remarks

If the artifact contains fewer than `n` lines, all available lines are returned. Matches the
behaviour of POSIX `head -n`.

#### Inherited from

[`SpooledArtifact`](../../../../spooled_artifact/classes/SpooledArtifact.md).[`head`](../../../../spooled_artifact/classes/SpooledArtifact.md#head)

***

### lineCount()

```ts
lineCount(): Promise<number>;
```

Defined in: [src/lib/classes/spooled\_artifact.ts:529](https://github.com/NHTIO/ADK/blob/v1.20260907.0/src/src/lib/classes/spooled_artifact.ts#L529)

Returns the total number of lines in the artifact.

#### Returns

`Promise`<`number`>

The line count as reported by the [@nhtio/adk!SpoolReader](../../../../spooled_artifact/interfaces/SpoolReader.md).

#### Inherited from

[`SpooledArtifact`](../../../../spooled_artifact/classes/SpooledArtifact.md).[`lineCount`](../../../../spooled_artifact/classes/SpooledArtifact.md#linecount)

***

### tail()

```ts
tail(n?: number): Promise<string[]>;
```

Defined in: [src/lib/classes/spooled\_artifact.ts:424](https://github.com/NHTIO/ADK/blob/v1.20260907.0/src/src/lib/classes/spooled_artifact.ts#L424)

Returns the last `n` lines of the artifact.

#### Parameters

| Parameter | Type     | Default value | Description                                |
| --------- | -------- | ------------- | ------------------------------------------ |
| `n`       | `number` | `10`          | Number of lines to return. Defaults to 10. |

#### Returns

`Promise`<`string`\[]>

Array of line strings, without trailing newlines.

#### Remarks

If the artifact contains fewer than `n` lines, all available lines are returned. Matches the
behaviour of POSIX `tail -n`.

#### Inherited from

[`SpooledArtifact`](../../../../spooled_artifact/classes/SpooledArtifact.md).[`tail`](../../../../spooled_artifact/classes/SpooledArtifact.md#tail)

***

### yaml\_filter()

```ts
yaml_filter(path: string): Promise<unknown[]>;
```

Defined in: [src/batteries/artifacts/yaml/index.ts:408](https://github.com/NHTIO/ADK/blob/v1.20260907.0/src/src/batteries/artifacts/yaml/index.ts#L408)

Returns documents matched by a JSONPath filter expression.

#### Parameters

| Parameter | Type     | Description                                                   |
| --------- | -------- | ------------------------------------------------------------- |
| `path`    | `string` | A JSONPath expression (e.g. `'$[?(@.status === "active")]'`). |

#### Returns

`Promise`<`unknown`\[]>

Array of matching documents.

#### Remarks

Evaluates `path` against each document and returns those for which the expression
produces at least one match.

***

### yaml\_get()

```ts
yaml_get(path: string): Promise<unknown[]>;
```

Defined in: [src/batteries/artifacts/yaml/index.ts:393](https://github.com/NHTIO/ADK/blob/v1.20260907.0/src/src/batteries/artifacts/yaml/index.ts#L393)

Evaluates a JSONPath expression against the parsed documents.

#### Parameters

| Parameter | Type     | Description                                                        |
| --------- | -------- | ------------------------------------------------------------------ |
| `path`    | `string` | A JSONPath expression (e.g. `'$.user.address.city'`, `'$..name'`). |

#### Returns

`Promise`<`unknown`\[]>

Array of matched values. Empty array when no matches are found.

#### Remarks

For single-document: evaluates the expression against the root value.
For multi-document: evaluates the expression against each document and returns a flat
array of all matches across all documents.

Uses [JSONPath-Plus](https://github.com/JSONPath-Plus/JSONPath). Full JSONPath syntax is
supported.

***

### yaml\_keys()

```ts
yaml_keys(): Promise<string[] | undefined>;
```

Defined in: [src/batteries/artifacts/yaml/index.ts:347](https://github.com/NHTIO/ADK/blob/v1.20260907.0/src/src/batteries/artifacts/yaml/index.ts#L347)

Returns the top-level keys of the parsed content.

#### Returns

`Promise`<`string`\[] | `undefined`>

Array of key strings, or `undefined` when no object keys are present.

#### Remarks

For single-document: returns the keys of the root object, or `undefined` when the root
is not a plain object.
For multi-document: returns the union of keys across all documents that are plain objects.
Duplicate keys are deduplicated.

***

### yaml\_length()

```ts
yaml_length(): Promise<number>;
```

Defined in: [src/batteries/artifacts/yaml/index.ts:374](https://github.com/NHTIO/ADK/blob/v1.20260907.0/src/src/batteries/artifacts/yaml/index.ts#L374)

Returns the total number of documents in the artifact.

#### Returns

`Promise`<`number`>

The document count.

#### Remarks

The result comes directly from js-yaml.loadAll(). For sources with no actual YAML content
(empty, whitespace-only, or BOM-only), the parser typically returns 0 documents, but certain
whitespace arrangements (such as a bare double newline) may yield 1. Do not rely on the exact
count to test for emptiness. For real documents, the count is reliable: a single-document
YAML returns 1, and a `---`-separated stream returns its exact document count.

***

### yaml\_pluck()

```ts
yaml_pluck(path: string): Promise<unknown[]>;
```

Defined in: [src/batteries/artifacts/yaml/index.ts:441](https://github.com/NHTIO/ADK/blob/v1.20260907.0/src/src/batteries/artifacts/yaml/index.ts#L441)

Returns all values matched by a JSONPath expression across every document.

#### Parameters

| Parameter | Type     | Description                               |
| --------- | -------- | ----------------------------------------- |
| `path`    | `string` | A JSONPath expression (e.g. `'$..name'`). |

#### Returns

`Promise`<`unknown`\[]>

Array of matched values.

#### Remarks

Convenience over [yaml\_get](#yaml_get) with an identical signature — use whichever name
better communicates intent at the call site.

***

### yaml\_slice()

```ts
yaml_slice(start?: number, end?: number): Promise<unknown[]>;
```

Defined in: [src/batteries/artifacts/yaml/index.ts:426](https://github.com/NHTIO/ADK/blob/v1.20260907.0/src/src/batteries/artifacts/yaml/index.ts#L426)

Returns a slice of documents by index range.

#### Parameters

| Parameter | Type     | Description                                            |
| --------- | -------- | ------------------------------------------------------ |
| `start?`  | `number` | Start index (inclusive). Defaults to `0`.              |
| `end?`    | `number` | End index (exclusive). Defaults to the document count. |

#### Returns

`Promise`<`unknown`\[]>

Array of sliced documents.

#### Remarks

Behaves like `Array.prototype.slice` over the document array.

***

### yaml\_type()

```ts
yaml_type(): Promise<"single-document" | "multi-document">;
```

Defined in: [src/batteries/artifacts/yaml/index.ts:328](https://github.com/NHTIO/ADK/blob/v1.20260907.0/src/src/batteries/artifacts/yaml/index.ts#L328)

Returns whether this artifact contains a single document or multiple documents.

#### Returns

`Promise`<`"single-document"` | `"multi-document"`>

`'single-document'` or `'multi-document'`.

#### Remarks

When the constructor was given `multiDocument: true`, the source is treated as a stream and
this reports `'multi-document'` even if that stream currently holds one document — a
one-element stream is still a stream, and [SpooledYamlArtifact.yaml\_length](#yaml_length) reports the
real count either way. `multiDocument: false` cannot disagree with the count, because parsing
a `---` stream under it fails outright rather than silently reporting the wrong mode.

***

### \[DECODE\_METHOD]\()

```ts
static DECODE_METHOD: SpooledYamlArtifact;
```

Defined in: [src/batteries/artifacts/yaml/index.ts:466](https://github.com/NHTIO/ADK/blob/v1.20260907.0/src/src/batteries/artifacts/yaml/index.ts#L466)

Reconstruct a SpooledYamlArtifact from a SpooledYamlArtifact.\[ENCODE\_METHOD]
snapshot.

#### Parameters

| Parameter | Type      | Description                                                     |
| --------- | --------- | --------------------------------------------------------------- |
| `data`    | `unknown` | The snapshot produced by SpooledYamlArtifact.\[ENCODE\_METHOD]. |

#### Returns

`SpooledYamlArtifact`

A fresh SpooledYamlArtifact} backed by a freshly-resolved reader.

#### Inherited from

[`SpooledArtifact`](../../../../spooled_artifact/classes/SpooledArtifact.md).[`[DECODE_METHOD]`](../../../../spooled_artifact/classes/SpooledArtifact.md#decode_method)

***

### \[DECODE\_METHOD]\()

```ts
static DECODE_METHOD: SpooledArtifact;
```

Defined in: [src/lib/classes/spooled\_artifact.ts:328](https://github.com/NHTIO/ADK/blob/v1.20260907.0/src/src/lib/classes/spooled_artifact.ts#L328)

Reconstruct a [SpooledArtifact](../../../../spooled_artifact/classes/SpooledArtifact.md) from an SpooledArtifact.\[ENCODE\_METHOD] snapshot.

#### Parameters

| Parameter | Type      | Description                                                 |
| --------- | --------- | ----------------------------------------------------------- |
| `data`    | `unknown` | The snapshot produced by SpooledArtifact.\[ENCODE\_METHOD]. |

#### Returns

[`SpooledArtifact`](../../../../spooled_artifact/classes/SpooledArtifact.md)

A fresh [SpooledArtifact](../../../../spooled_artifact/classes/SpooledArtifact.md) backed by a freshly-resolved reader.

#### Remarks

Re-binds the reader via @nhtio/adk!resolveSpoolReader; throws
[@nhtio/adk!E\_NO\_READER\_RESOLVER](../../../../exceptions/variables/E_NO_READER_RESOLVER.md) when no resolver is registered for the descriptor's tag.

#### Inherited from

```ts
SpooledArtifact.[DECODE_METHOD]
```

***

### forgeTools()

```ts
static forgeTools(ctx: DispatchContext): ToolRegistry;
```

Defined in: [src/batteries/artifacts/yaml/index.ts:216](https://github.com/NHTIO/ADK/blob/v1.20260907.0/src/src/batteries/artifacts/yaml/index.ts#L216)

Forges base-class tools plus YAML-specific tools narrowed to SpooledYamlArtifact.

#### Parameters

| Parameter | Type                                                                 |
| --------- | -------------------------------------------------------------------- |
| `ctx`     | [`DispatchContext`](../../../../types/interfaces/DispatchContext.md) |

#### Returns

[`ToolRegistry`](../../../../forge/classes/ToolRegistry.md)

#### Remarks

Standard subclass extension pattern: call `SpooledArtifact.forgeTools(ctx)` to produce
the base seven `artifact_*` tools narrowed to any `SpooledArtifact` in the turn, then
register one `ArtifactTool` per YAML-specific descriptor narrowed to YAML artifacts.

#### Overrides

[`SpooledArtifact`](../../../../spooled_artifact/classes/SpooledArtifact.md).[`forgeTools`](../../../../spooled_artifact/classes/SpooledArtifact.md#forgetools)

***

### isSpooledArtifact()

```ts
static isSpooledArtifact(value: unknown): value is SpooledArtifact;
```

Defined in: [src/lib/classes/spooled\_artifact.ts:361](https://github.com/NHTIO/ADK/blob/v1.20260907.0/src/src/lib/classes/spooled_artifact.ts#L361)

Returns `true` if `value` is a [SpooledArtifact](../../../../spooled_artifact/classes/SpooledArtifact.md) instance (including any subclass).

#### Parameters

| Parameter | Type      | Description        |
| --------- | --------- | ------------------ |
| `value`   | `unknown` | The value to test. |

#### Returns

`value is SpooledArtifact`

`true` when `value` is a [SpooledArtifact](../../../../spooled_artifact/classes/SpooledArtifact.md) instance.

#### Remarks

Uses the cross-realm-safe [@nhtio/adk!isInstanceOf](../../../../guards/functions/isInstanceOf.md) guard: `instanceof` first, then
`Symbol.hasInstance`, then a `constructor.name` fallback. Subclass instances (e.g.
[@nhtio/adk!SpooledJsonArtifact](../../../../spooled_artifact/classes/SpooledJsonArtifact.md)) satisfy this guard because `instanceof` walks the prototype
chain. The fallbacks handle the dual-module-copy case where two distinct `SpooledArtifact`
classes coexist in the same realm (e.g. one bundled into a downstream library, one in the
consumer's `node_modules`).

#### Inherited from

[`SpooledArtifact`](../../../../spooled_artifact/classes/SpooledArtifact.md).[`isSpooledArtifact`](../../../../spooled_artifact/classes/SpooledArtifact.md#isspooledartifact)

***

### isSpooledArtifactConstructor()

```ts
static isSpooledArtifactConstructor(value: unknown): value is SpooledArtifactConstructor<SpooledArtifact>;
```

Defined in: [src/lib/classes/spooled\_artifact.ts:378](https://github.com/NHTIO/ADK/blob/v1.20260907.0/src/src/lib/classes/spooled_artifact.ts#L378)

Returns `true` if `value` is a constructor function whose prototype chain includes
[SpooledArtifact](../../../../spooled_artifact/classes/SpooledArtifact.md) (including `SpooledArtifact` itself).

#### Parameters

| Parameter | Type      | Description        |
| --------- | --------- | ------------------ |
| `value`   | `unknown` | The value to test. |

#### Returns

`value is SpooledArtifactConstructor<SpooledArtifact>`

`true` when `value` is a constructor for `SpooledArtifact` or a subclass.

#### Remarks

Used by [@nhtio/adk!Tool](../../../../forge/classes/Tool.md) to validate the optional `artifactConstructor` field. Performs an
`instanceof`-based check on the prototype chain; falls back to a duck-type test that looks
for the canonical SpooledArtifact instance methods on `value.prototype` for cross-realm
safety (constructors passed from a different module copy or VM context).

#### Inherited from

[`SpooledArtifact`](../../../../spooled_artifact/classes/SpooledArtifact.md).[`isSpooledArtifactConstructor`](../../../../spooled_artifact/classes/SpooledArtifact.md#isspooledartifactconstructor)

***

### isSpooledYamlArtifact()

```ts
static isSpooledYamlArtifact(value: unknown): value is SpooledYamlArtifact;
```

Defined in: [src/batteries/artifacts/yaml/index.ts:126](https://github.com/NHTIO/ADK/blob/v1.20260907.0/src/src/batteries/artifacts/yaml/index.ts#L126)

Returns `true` if `value` is a SpooledYamlArtifact instance.

#### Parameters

| Parameter | Type      | Description        |
| --------- | --------- | ------------------ |
| `value`   | `unknown` | The value to test. |

#### Returns

`value is SpooledYamlArtifact`

`true` when `value` is a SpooledYamlArtifact instance.

#### Remarks

Uses the cross-realm-safe [@nhtio/adk!isInstanceOf](../../../../guards/functions/isInstanceOf.md) guard. Safe against the
dual-module-copy case where two distinct `SpooledYamlArtifact` classes coexist in the
same realm.