backend.ts

import type { JSONSchema7Object } from "json-schema"
import type { OpenAIOutput } from "./types"

/**
 * Provider-agnostic LLM backend interface used by the summarizer and
 * location parser. Implementations include {@link createOpenAiBackend} and
 * {@link createAnthropicBackend}; consumers can also supply their own (e.g.
 * an Azure OpenAI gateway, a Bedrock adapter, a deterministic fake for
 * tests) as long as they satisfy this shape.
 *
 * Instances are produced by factory functions so API keys and model choices
 * live in consumer code, never in module-level state.
 */
export interface LlmBackend {
    readonly model: string
    readonly tokenLimit: number
    countTokens(text: string): number
    chatCompletion(content: string): Promise<OpenAIOutput<string>>
    chatFunctionJson<T>(
        systemMessage: string,
        userMessage: string,
        schema: JSONSchema7Object,
        functionName: string,
    ): Promise<OpenAIOutput<T>>
}