Add support for Anthropic models

src/models/anthropic/messages.ts

@@ -0,0 +1,385 @@
+import { Model } from "../..";
+import { JSON } from "json-as";
+
+/**
+ * Provides input and output types that conform to the Anthropic Messages API.
+ *
+ * Reference: https://docs.anthropic.com/en/api/messages
+ */
+export class AnthropicMessagesModel extends Model<
+  AnthropicMessagesInput,
+  AnthropicMessagesOutput
+> {
+  /**
+   * Creates an input object for the Anthropic Messages API.
+   *
+   * @param messages: An array of messages to send to the model.
+   * Note that if you want to include a system prompt, you can use the top-level system parameter —
+   * there is no "system" role for input messages in the Messages API.
+   * @returns An input object that can be passed to the `invoke` method.
+   */
+  createInput(messages: Message[]): AnthropicMessagesInput {
+    const model = this.info.fullName;
+    return <AnthropicMessagesInput>{ model, messages };
+  }
+}
+
+/**
+ * A message object that can be sent to the model.
+ */
+@json
+export class Message {
+  /**
+   * Creates a new message object.
+   *
+   * @param role The role of the author of this message.
+   * @param content The contents of the message.
+   */
+  constructor(role: string, content: string) {
+    this._role = role;
+    this.content = content;
+  }
+
+
+  @alias("role")
+  protected _role: string;
+
+  /**
+   * The role of the author of this message.
+   */
+  get role(): string {
+    return this._role;
+  }
+
+  /**
+   * The contents of the message.
+   * For now it can only be a string, even though Anthropic supports more complex types.
+   */
+  content: string; // TODO: support more complex types
+}
+
+/**
+ * A user message.
+ */
+@json
+export class UserMessage extends Message {
+  /**
+   * Creates a new user message object.
+   *
+   * @param content The contents of the message.
+   */
+  constructor(content: string) {
+    super("user", content);
+  }
+}
+
+/**
+ * An assistant message.
+ */
+@json
+export class AssistantMessage extends Message {
+  /**
+   * Creates a new assistant message object.
+   *
+   * @param content The contents of the message.
+   */
+  constructor(content: string) {
+    super("assistant", content);
+  }
+}
+
+/**
+ * The input object for the Anthropic Messages API.
+ */
+@json
+class AnthropicMessagesInput {
+  /**
+   * The model that will complete your prompt.
+   * Must be the exact string expected by the model provider.
+   * For example, "claude-3-5-sonnet-20240620".
+   *
+   * See [models](https://docs.anthropic.com/en/docs/models-overview) for additional
+   * details and options.
+   *
+   * @remarks
+   * This field is automatically set by the `createInput` method when creating this object.
+   * It does not need to be set manually.
+   */
+  model!: string;
+
+  /**
+   * Input messages.
+   *
+   * We do not currently support image content blocks, which are available starting with
+   * Claude 3 models. This will be added in a future release.
+   *
+   * Note that if you want to include a
+   * [system prompt](https://docs.anthropic.com/en/docs/system-prompts), you can use
+   * the top-level `system` parameter — there is no `"system"` role for input
+   * messages in the Messages API.
+   */
+  messages!: Message[];
+
+  /**
+   * The maximum number of tokens to generate before stopping.
+   *
+   * Different models have different maximum values for this parameter. See
+   * [models](https://docs.anthropic.com/en/docs/models-overview) for details.
+   *
+   * @default 4096
+   */
+  @alias("max_tokens")
+  maxTokens: i32 = 4096;
+
+  /**
+   * A `Metadata` object describing the request.
+   */
+  @omitnull()
+  metadata: Metadata | null = null;
+
+  /**
+   * Custom text sequences that will cause the model to stop generating.
+   */
+  @alias("stop_sequences")
+  @omitnull()
+  stopSequences: string[] | null = null;
+
+  /**
+   * Streaming is not currently supported.
+   *
+   * @default false
+   */
+  @alias("stream")
+  @omitif("this._stream == false")
+  private _stream: boolean = false;
+
+  /**
+   * System prompt.
+   *
+   * A system prompt is a way of providing context and instructions to Claude, such
+   * as specifying a particular goal or role. See [guide to system prompts](https://docs.anthropic.com/en/docs/system-prompts).
+   */
+  @omitnull()
+  system: string | null = null;
+
+  /**
+   * A number between `0.0` and `1.0` that controls the randomness injected into the response.
+   *
+   * It is recommended to use `temperature` closer to `0.0`
+   * for analytical / multiple choice, and closer to `1.0` for creative tasks.
+   *
+   * Note that even with `temperature` of `0.0`, the results will not be fully
+   * deterministic.
+   *
+   * @default 1.0
+   */
+  @omitif("this.temperature == 1.0")
+  temperature: f64 = 1.0;
+
+  /**
+   * How the model should use the provided tools.
+   *
+   * Use either `ToolChoiceAuto`, `ToolChoiceAny`, or `ToolChoiceTool(name: string)`.
+   */
+  @alias("tool_choice")
+  @omitnull()
+  toolChoice: ToolChoice | null = null;
+
+  /**
+   * Definitions of tools that the model may use.
+   *
+   * Tools can be used for workflows that include running client-side tools and
+   * functions, or more generally whenever you want the model to produce a particular
+   * JSON structure of output.
+   *
+   * See Anthropic's [guide](https://docs.anthropic.com/en/docs/tool-use) for more details.
+   */
+  @omitnull()
+  tools: Tool[] | null = null;
+
+  /**
+   * Only sample from the top K options for each subsequent token.
+   *
+   * Recommended for advanced use cases only. You usually only need to use
+   * `temperature`.
+   */
+  @alias("top_k")
+  @omitif("this.topK == -1")
+  topK: i64 = -1; // The default value of top_k is not specified in the API docs
+
+  /**
+   * Use nucleus sampling.
+   *
+   * You should either alter `temperature` or `top_p`, but not both.
+   *
+   * Recommended for advanced use cases only. You usually only need to use
+   * `temperature`.
+   */
+  @alias("top_p")
+  @omitif("this.topP == 0.999")
+  topP: f64 = 0.999;
+}
+
+
+@json
+export class Metadata {
+  /**
+   * An external identifier for the user who is associated with the request.
+   */
+  @alias("user_id")
+  userId: string | null = null;
+}
+
+/**
+ * A tool object that the model may call.
+ */
+@json
+export class Tool {
+  /**
+   * Name of the tool.
+   */
+  name!: string;
+
+  /**
+   * [JSON schema](https://json-schema.org/) for this tool's input.
+   *
+   * This defines the shape of the `input` that your tool accepts and that the model
+   * will produce.
+   */
+  @alias("input_schema")
+  inputSchema!: JSON.Raw;
+
+  /**
+   * Optional, but strongly-recommended description of the tool.
+   */
+  @omitnull()
+  description: string | null = null;
+}
+
+
+@json
+class ToolChoice {
+  constructor(type: string, name: string | null = null) {
+    this._type = type;
+    this._name = name;
+  }
+
+
+  @alias("type")
+  protected _type: string;
+
+  /**
+   * The name of the tool to use.
+   */
+  @alias("name")
+  @omitnull()
+  protected _name: string | null = null;
+}
+
+/**
+ * The model will automatically decide whether to use tools.
+ */
+export const ToolChoiceAuto = new ToolChoice("auto");
+
+/**
+ * The model will use any available tools.
+ */
+export const ToolChoiceAny = new ToolChoice("any");
+
+/**
+ * The model will use the specified tool.
+ */
+export const ToolChoiceTool = (name: string): ToolChoice =>
+  new ToolChoice("tool", name);
+
+/**
+ * The output object for the Anthropic Messages API.
+ */
+@json
+class AnthropicMessagesOutput {
+  /**
+   * Unique object identifier.
+   */
+  id!: string;
+
+  /**
+   * Content generated by the model.
+   *
+   */
+  content!: ContentBlock[];
+
+  /**
+   * The model that handled the request.
+   */
+  model!: string;
+
+  /**
+   * Conversational role of the generated message.
+   *
+   * This will always be `"assistant"`.
+   */
+  role!: "assistant";
+
+  /**
+   * The reason that the model stopped.
+   */
+  @alias("stop_reason")
+  stopReason!: string;
+
+  /**
+   * Which custom stop sequence was generated, if any.
+   *
+   * This value will be a non-null string if one of your custom stop sequences was
+   * generated.
+   */
+  @alias("stop_sequence")
+  stopSequence: string | null = null;
+
+  /**
+   * Object type. This is always `"message"`.
+   */
+  type!: "message";
+
+  /**
+   * Billing and rate-limit usage.
+   */
+  usage!: Usage;
+}
+
+
+@json
+class ContentBlock {
+  type!: string;
+
+  // Text block
+  @omitnull()
+  text: string | null = null;
+
+  // Tool use block
+  @omitnull()
+  id: string | null = null;
+
+
+  @omitnull()
+  input: JSON.Raw | null = null;
+
+
+  @omitnull()
+  name: string | null = null;
+}
+
+
+@json
+class Usage {
+  /**
+   * The number of input tokens which were used.
+   */
+  @alias("input_tokens")
+  inputTokens!: number;
+
+  /**
+   * The number of output tokens which were used.
+   */
+  @alias("output_tokens")
+  outputTokens!: number;
+}