createVectorBuilder() API reference

Create a builder that binds inferred Runtime Configuration and computed Context types to every Vector definition and extension helper.

Import createVectorBuilder() from @evilkiwi/vector.

function createVectorBuilder<Computed extends object>(options: {
  computeContext(input: ComputeContextInput): Computed;
}): VectorBuilder<Record<never, never>, Computed>;

function createVectorBuilder<Schema extends StandardSchemaV1>(options: {
  runtimeConfig: { slug: string; schema: Schema };
}): VectorBuilder<StandardSchemaV1.InferOutput<Schema>>;

function createVectorBuilder<Schema extends StandardSchemaV1, Computed extends object>(options: {
  runtimeConfig: { slug: string; schema: Schema };
  computeContext(input: ComputeContextInput): Computed;
}): VectorBuilder<StandardSchemaV1.InferOutput<Schema>, Computed>;

function createVectorBuilder(): VectorBuilder;

runtimeConfig contains the filesystem-safe slug and Standard Schema used for every Vector Configuration defined by the builder. The schema output becomes the builder’s inferred Runtime Configuration type. Vector captures this metadata when createVectorBuilder() runs.

computeContext runs once for each plugin activation after Runtime Configuration validation. It receives only the active location fields through ComputeContextInput; Runtime Configuration is not available to this callback. Vector merges its returned properties into the Context passed to the bound defineVector() and extension callbacks.

The builder exposes bound defineVector, defineAgent, defineCatalogProvider, defineCommand, defineIntegration, defineIntegrationMethod, defineMCPServer, defineModel, defineReference, defineSkill, defineTool, and defineWebSearchProvider helpers. Definitions from one builder share its Runtime Configuration and computed Context types and can be selected by multiple Vector Configurations. Each activation resolves separate runtime values.

Extension helpers do not accept a Runtime Configuration generic. Define extensions through the builder that owns their Runtime Configuration schema.

const projectSummary = vector.defineCommand({
  name: 'project-summary',
  build: (context) => ({
    template: `Summarize ${context.projectLabel} for ${context.runtimeConfig.audience}`,
  }),
});

The computed result must be a synchronous plain object. Object literals, explicitly typed interfaces, and null-prototype records are accepted. Arrays, dates, class instances, Promise-like values, and the reserved runtimeConfig, cwd, or project keys are rejected. A non-callable then property is an ordinary Context property.

Validation, callback execution, and flat merge use one guarded boundary. A violation or a property getter that throws fails activation before the root build() callback, extension materialization, or host registration. An Error thrown by computeContext remains that error; other thrown values receive a safe message.

Calling createVectorBuilder() without options provides the same no-config, no-computed-context helpers as the root named helpers. Vector skips Runtime Configuration discovery and supplies a fresh mutable empty object for each activation. See Context for Context and ComputeContextInput.