@llm-ports/adapter-anthropic

Direct adapter for the Anthropic SDK. Implements LLMPort for Claude models. Does NOT implement EmbeddingsPort — Anthropic ships no embedding models.

Install

pnpm add @llm-ports/core @llm-ports/adapter-anthropic @anthropic-ai/sdk zod

Configure

import { createRegistryFromEnv } from "@llm-ports/core";
import { createAnthropicAdapter } from "@llm-ports/adapter-anthropic";

const registry = createRegistryFromEnv({
  adapters: {
    anthropic: createAnthropicAdapter({
      apiKey: process.env.ANTHROPIC_API_KEY!,
    }),
  },
});

export const llm = registry.getPort();

.env:

LLM_PROVIDER_FAST=anthropic|claude-haiku-4-5|cost:5/day
LLM_PROVIDER_PREMIUM=anthropic|claude-sonnet-4-6-20250514|cost:50/day
LLM_TASK_ROUTE_TRIAGE=fast,premium

Adapter options

interface AnthropicAdapterOptions {
  apiKey: string;
  baseURL?: string;          // typically only useful for testing
  fetch?: typeof fetch;       // inject a custom fetch (tests, proxies)
  validationStrategy?: ValidationStrategy;
  pricingOverrides?: Record<string, ModelPricing>;
}

Bundled pricing

Model	Input/1M	Output/1M	Cache read	Cache write
claude-opus-4	$15.00	$75.00	$1.50	$18.75
claude-sonnet-4-6-20250514	$3.00	$15.00	$0.30	$3.75
claude-sonnet-4-5	$3.00	$15.00	$0.30	$3.75
claude-haiku-4-5	$0.80	$4.00	$0.08	$1.00

Source: anthropic.com/pricing. Verified 2026-04-10.

Override per model via pricingOverrides if prices change between releases:

createAnthropicAdapter({
  apiKey: process.env.ANTHROPIC_API_KEY!,
  pricingOverrides: {
    "claude-sonnet-4-6-20250514": { inputPer1M: 3.5, outputPer1M: 17.5 },
  },
});

Supported features

Feature	Status
generateText	✓
generateStructured (Zod schemas)	✓ (prompted JSON + retry-with-feedback)
streamText	✓
streamStructured	✓ (best-effort partial parse)
runAgent (multi-turn tool use)	✓
Vision input — base64 images	✓
Vision input — URL images	✓
Audio input	✗ (Anthropic chat doesn't support audio)
Prompt caching	✓ native; cost reflects cacheReadPer1M rate
Embeddings	✗ (Anthropic ships no embedding models)

Content blocks supported

text, image (base64 + URL), tool_use, tool_result. The adapter throws ContentBlockUnsupportedError for audio blocks.

Reading next

• Tool-use security guide — runAgent code patterns, the destructive / requiresConfirmation / maxOutputBytes flags, the approval-gate wrapper
• Content blocks reference — tool_use and tool_result block shapes
• Anthropic prompt caching docs — how cache reads are billed
• Pricing source — verify the bundled table is current