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Class: SpooledEcmaScriptArtifact ​

Defined in: src/batteries/artifacts/ecmascript/index.ts:166

A @nhtio/adk!SpooledArtifact specialisation for EcmaScript (JavaScript and TypeScript) source files.

Remarks ​

Parses source code syntactically (no type checker) using the TypeScript compiler API, enabling structural queries without materialising the full file into memory.

The parser automatically infers the script kind (.js, .ts, .jsx, .tsx) from the fileName when provided; defaults to ts when omitted (it parses the widest grammar).

All parsing errors are non-fatal — TypeScript's parser is error-tolerant and produces a partial tree. Diagnostics are not surfaced by the query methods.

Extends ​

Constructors ​

Constructor ​

ts
new SpooledEcmaScriptArtifact(reader: SpoolReader, options?: {
  fileName?: string;
  scriptKind?: "js" | "jsx" | "ts" | "tsx";
}): SpooledEcmaScriptArtifact;

Defined in: src/batteries/artifacts/ecmascript/index.ts:180

Parameters ​

ParameterTypeDescription
readerSpoolReaderThe backing store to read from.
options?{ fileName?: string; scriptKind?: "js" | "jsx" | "ts" | "tsx"; }Optional configuration.
options.fileName?stringThe source file name. When provided, script kind is inferred from the extension (.mts/.cts/.ts → 'ts', .mjs/.cjs/.js → 'js', .tsx → 'tsx', .jsx → 'jsx'). Defaults to undefined.
options.scriptKind?"js" | "jsx" | "ts" | "tsx"Explicit script kind override. Defaults to 'ts' when not provided and cannot be inferred from fileName.

Returns ​

SpooledEcmaScriptArtifact

Overrides ​

SpooledArtifact.constructor

Properties ​

PropertyModifierTypeDescriptionOverridesDefined in
toolMethodsstaticreadonly ToolMethodDescriptor[]The EcmaScript-specific artifact-query descriptors this class adds. Remarks Lists seven descriptors; the base seven (artifact_head, etc.) are forged separately.SpooledArtifact.toolMethodssrc/batteries/artifacts/ecmascript/index.ts:209

Methods ​

[ENCODE_METHOD]() ​

ts
ENCODE_METHOD: unknown;

Defined in: src/batteries/artifacts/ecmascript/index.ts:1135

Serialise this SpooledEcmaScriptArtifact into an encoder snapshot.

Returns ​

unknown

Inherited from ​

SpooledArtifact.[ENCODE_METHOD]


[ENCODE_METHOD]() ​

ts
ENCODE_METHOD: unknown;

Defined in: src/lib/classes/spooled_artifact.ts:361

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; decode re-binds the reader through the registered resolver. Throws @nhtio/adk!E_READER_NOT_DESCRIBABLE when the reader cannot describe itself. Subclasses override this to include their own discriminators (e.g. @nhtio/adk!SpooledJsonArtifact adds format).

Inherited from ​

ts
SpooledArtifact.[ENCODE_METHOD]

asString() ​

ts
asString(): Promise<string>;

Defined in: src/lib/classes/spooled_artifact.ts:677

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 was constructed over — preserves trailing newlines and non-\n line terminators that SpooledArtifact.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.asString


byteLength() ​

ts
byteLength(): Promise<number>;

Defined in: src/lib/classes/spooled_artifact.ts:548

Returns the total byte length of the underlying data.

Returns ​

Promise<number>

The byte length as reported by the @nhtio/adk!SpoolReader.

Inherited from ​

SpooledArtifact.byteLength


cat() ​

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

Defined in: src/lib/classes/spooled_artifact.ts:529

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

Parameters ​

ParameterTypeDescription
start?number0-based start line index (inclusive). Defaults to 0.
end?number0-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 / SpooledArtifact.tail.

Inherited from ​

SpooledArtifact.cat


es_exports() ​

ts
es_exports(): Promise<EcmaScriptExport[]>;

Defined in: src/batteries/artifacts/ecmascript/index.ts:578

Return every export declaration and re-export.

Returns ​

Promise<EcmaScriptExport[]>


es_imports() ​

ts
es_imports(): Promise<EcmaScriptImport[]>;

Defined in: src/batteries/artifacts/ecmascript/index.ts:520

Return every import declaration.

Returns ​

Promise<EcmaScriptImport[]>


es_jsdoc() ​

ts
es_jsdoc(name: string): Promise<string>;

Defined in: src/batteries/artifacts/ecmascript/index.ts:1077

Return the JSDoc comment for a named declaration. Searches top-level declarations (functions, classes, interfaces, enums, type aliases, const/let/var bindings), class members (methods, properties, constructors, accessors), and interface members (method signatures, property signatures) — the same lookup SpooledEcmaScriptArtifact.es_signature uses, so the two always agree on what a name resolves to.

Parameters ​

ParameterType
namestring

Returns ​

Promise<string>


es_outline() ​

ts
es_outline(): Promise<OutlineEntry[]>;

Defined in: src/batteries/artifacts/ecmascript/index.ts:703

Return a structural outline of classes and interfaces with their members.

Returns ​

Promise<OutlineEntry[]>


es_references() ​

ts
es_references(name: string): Promise<IdentifierReference[]>;

Defined in: src/batteries/artifacts/ecmascript/index.ts:1109

Return every line where an identifier appears (syntactic scan only).

Parameters ​

ParameterType
namestring

Returns ​

Promise<IdentifierReference[]>


es_signature() ​

ts
es_signature(name: string): Promise<string>;

Defined in: src/batteries/artifacts/ecmascript/index.ts:1059

Return the signature text for a named declaration. Searches top-level declarations (functions, classes, interfaces, enums, type aliases, const/let/var bindings), class members (methods, properties, constructors, accessors), and interface members (method signatures, property signatures) — the same lookup SpooledEcmaScriptArtifact.es_jsdoc uses, so the two always agree on what a name resolves to.

Parameters ​

ParameterType
namestring

Returns ​

Promise<string>


es_symbols() ​

ts
es_symbols(kind?: string): Promise<EcmaScriptSymbol[]>;

Defined in: src/batteries/artifacts/ecmascript/index.ts:419

Return every top-level declaration, optionally filtered by kind.

Parameters ​

ParameterType
kind?string

Returns ​

Promise<EcmaScriptSymbol[]>


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:594

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 ​

ParameterTypeDescription
callIdstringThe 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; }) => stringOptional renderer overriding the interim default.

Returns ​

number

A synchronous token estimate.

Inherited from ​

SpooledArtifact.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:656

Estimates the total token count of the artifact under encoding.

Parameters ​

ParameterTypeDescription
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 (which delegates to @nhtio/adk!SpoolReader.readAll) and delegates to @nhtio/adk!Tokenizable.estimateTokens. The estimate therefore reflects the actual source bytes — including trailing newlines and non-\n line terminators that the line-based SpooledArtifact.cat view would otherwise discard or misrepresent.

Inherited from ​

SpooledArtifact.estimateTokens


grep() ​

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

Defined in: src/lib/classes/spooled_artifact.ts:501

Returns all lines that match pattern.

Parameters ​

ParameterTypeDescription
patternRegExpThe 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.grep


hasSizeHints() ​

ts
hasSizeHints(): boolean;

Defined in: src/lib/classes/spooled_artifact.ts:567

Returns whether producer-computed size metadata is available.

Returns ​

boolean

true when SpooledArtifact._setSizeHints has populated the cache.

Inherited from ​

SpooledArtifact.hasSizeHints


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

Defined in: src/lib/classes/spooled_artifact.ts:448

Returns the first n lines of the artifact.

Parameters ​

ParameterTypeDefault valueDescription
nnumber10Number 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.head


lineCount() ​

ts
lineCount(): Promise<number>;

Defined in: src/lib/classes/spooled_artifact.ts:576

Returns the total number of lines in the artifact.

Returns ​

Promise<number>

The line count as reported by the @nhtio/adk!SpoolReader.

Inherited from ​

SpooledArtifact.lineCount


tail() ​

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

Defined in: src/lib/classes/spooled_artifact.ts:471

Returns the last n lines of the artifact.

Parameters ​

ParameterTypeDefault valueDescription
nnumber10Number 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.tail


[DECODE_METHOD]() ​

ts
static DECODE_METHOD: SpooledEcmaScriptArtifact;

Defined in: src/batteries/artifacts/ecmascript/index.ts:1146

Reconstruct a SpooledEcmaScriptArtifact from an encoder snapshot.

Parameters ​

ParameterType
dataunknown

Returns ​

SpooledEcmaScriptArtifact

Inherited from ​

SpooledArtifact.[DECODE_METHOD]


[DECODE_METHOD]() ​

ts
static DECODE_METHOD: SpooledArtifact;

Defined in: src/lib/classes/spooled_artifact.ts:375

Reconstruct a SpooledArtifact from an SpooledArtifact.[ENCODE_METHOD] snapshot.

Parameters ​

ParameterTypeDescription
dataunknownThe snapshot produced by SpooledArtifact.[ENCODE_METHOD].

Returns ​

SpooledArtifact

A fresh SpooledArtifact backed by a freshly-resolved reader.

Remarks ​

Re-binds the reader via @nhtio/adk!resolveSpoolReader; throws @nhtio/adk!E_NO_READER_RESOLVER 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/ecmascript/index.ts:284

Forges base-class tools plus EcmaScript-specific tools narrowed to SpooledEcmaScriptArtifact.

Parameters ​

ParameterType
ctxDispatchContext

Returns ​

ToolRegistry

Overrides ​

SpooledArtifact.forgeTools


isSpooledArtifact() ​

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

Defined in: src/lib/classes/spooled_artifact.ts:408

Returns true if value is a SpooledArtifact instance (including any subclass).

Parameters ​

ParameterTypeDescription
valueunknownThe value to test.

Returns ​

value is SpooledArtifact

true when value is a SpooledArtifact instance.

Remarks ​

Uses the cross-realm-safe @nhtio/adk!isInstanceOf guard: instanceof first, then Symbol.hasInstance, then a constructor.name fallback. Subclass instances (e.g. @nhtio/adk!SpooledJsonArtifact) 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.isSpooledArtifact


isSpooledArtifactConstructor() ​

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

Defined in: src/lib/classes/spooled_artifact.ts:425

Returns true if value is a constructor function whose prototype chain includes SpooledArtifact (including SpooledArtifact itself).

Parameters ​

ParameterTypeDescription
valueunknownThe 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 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.isSpooledArtifactConstructor


isSpooledEcmaScriptArtifact() ​

ts
static isSpooledEcmaScriptArtifact(value: unknown): value is SpooledEcmaScriptArtifact;

Defined in: src/batteries/artifacts/ecmascript/index.ts:199

Returns true if value is a SpooledEcmaScriptArtifact instance.

Parameters ​

ParameterType
valueunknown

Returns ​

value is SpooledEcmaScriptArtifact

Remarks ​

Uses the cross-realm-safe @nhtio/adk!isInstanceOf guard. Safe against the dual-module-copy case.