@agentskit/adapters

Profile: major-package

Connect to any LLM provider — and swap between them — without touching your app code.

Tags: ai · agents · llm · agentskit · openai · anthropic · claude · gemini · chatgpt · ollama · embeddings · providers

Verified proof

• Package metadata and tests live under packages/adapters/.
• Package guide: https://www.agentskit.io/docs/reference/packages/adapters
• Stability map: docs/STABILITY.md

How this fits the ecosystem

@agentskit/adapters is the provider layer: swap OpenAI, Anthropic, Gemini, Ollama, local models, and embedding providers without rewriting your agent.

• AgentsKit: compose it with the other packages in this repo to build agents from small, swappable parts.
• Registry: look for ready agents and templates that already use this layer at registry.agentskit.io.
• Playbook: learn the production patterns behind this layer at playbook.agentskit.io.
• AKOS: run the same concepts with enterprise deployment, governance, and observability at akos.agentskit.io.

Docs: package guide · agent handoff

Why adapters

• Vendor independence — switch from OpenAI to Anthropic to a local Ollama model by changing one line; your hooks, runtime, and tools stay untouched
• 25 native adapters in the catalog — Anthropic, OpenAI, Gemini, Ollama, DeepSeek, Grok, Kimi, Mistral, Cohere, Together, Groq, Fireworks, OpenRouter, Hugging Face, LM Studio, vLLM, llama.cpp, LangChain, Vercel AI SDK, and additional compatible providers
• Embedder functions built in — the same adapter pattern covers text embeddings, so you can reuse provider config for both chat and RAG
• One-line local AI — ollama({ model: 'llama3.1' }) for fully offline agents with no API key required

Install

npm install @agentskit/adapters

The runtime example below also needs @agentskit/runtime. The RAG example also needs @agentskit/rag, @agentskit/memory, and the optional vectra peer (npm install @agentskit/rag @agentskit/memory vectra).

Quick example

import { anthropic } from '@agentskit/adapters'
import { createRuntime } from '@agentskit/runtime'

// Switch provider by swapping one import
const adapter = anthropic({ apiKey: process.env.ANTHROPIC_API_KEY, model: 'claude-sonnet-4-6' })
// const adapter = openai({ apiKey: process.env.OPENAI_API_KEY, model: 'gpt-4o' })
// const adapter = ollama({ model: 'llama3.1' })

const runtime = createRuntime({ adapter })
const result = await runtime.run('Summarize the latest AI news')
console.log(result.content)

Embeddings (for RAG)

Use the same package for vector embeddings — wire openaiEmbedder, geminiEmbedder, or ollamaEmbedder into @agentskit/rag:

import { openaiEmbedder } from '@agentskit/adapters'
import { createRAG } from '@agentskit/rag'
import { fileVectorMemory } from '@agentskit/memory'

const rag = createRAG({
  embed: openaiEmbedder({ apiKey: process.env.OPENAI_API_KEY! }),
  store: fileVectorMemory({ path: './vectors' }),
})

Features

• Providers: Anthropic, OpenAI, Gemini, Ollama, DeepSeek, Grok, Kimi, Mistral, Cohere, Together, Groq, Fireworks, OpenRouter, Hugging Face, LM Studio, vLLM, llama.cpp, LangChain, LangGraph, Vercel AI SDK, generic ReadableStream
• Embedders: openaiEmbedder, geminiEmbedder, ollamaEmbedder, deepseekEmbedder, grokEmbedder, kimiEmbedder, createOpenAICompatibleEmbedder
• Fetch-backed adapters run against the shared Adapter contract v1 suite (ADR 0001); SDK-backed adapters have provider-specific contract and resilience coverage
• Custom adapter authoring via createAdapter()
• Higher-order adapters: createRouter (cost/latency/classifier), createEnsembleAdapter (fan-out + merge), createFallbackAdapter (ordered try-next)

Stream guarantees

• A stream terminates exactly once with done or error; terminal errors carry an Error in metadata.error.
• Provider streams that close before their native completion marker are treated as truncated, not successful.
• abort(reason) propagates to active fetch readers and SDK requests and terminates with the same error semantics.
• Native tool histories preserve call/result correlation. Parallel tool results are encoded in a single provider turn where required.
• Credentials stay in provider headers when the protocol supports them; Gemini API keys are never placed in request URLs.
• vercelAI consumes the Vercel AI SDK UI message stream v1 protocol, including its required response header and [DONE] marker.

Higher-order adapters

import { createRouter, anthropic, openai } from '@agentskit/adapters'

// Auto-pick cheapest capable candidate per request.
const router = createRouter({
  candidates: [
    { id: 'haiku', adapter: anthropic({ model: 'claude-haiku-4-5' }), cost: 0.25 },
    { id: 'sonnet', adapter: anthropic({ model: 'claude-sonnet-4-6' }), cost: 3 },
    { id: 'gpt-mini', adapter: openai({ model: 'gpt-4o-mini' }), cost: 0.15 },
  ],
})

See Adapter router, Ensemble, and Fallback chain.

Ecosystem

| Package | Role | |---------|------| | @agentskit/core | Adapter, EmbedFn, types | | @agentskit/runtime | Headless createRuntime | | @agentskit/rag | createRAG + embedders | | @agentskit/memory | Vector + chat memory backends |

Testing Adapters

Three built-in utilities let you test agents without hitting a real LLM.

mockAdapter — deterministic responses

import { mockAdapter } from '@agentskit/adapters'

const adapter = mockAdapter({
  response: [
    { type: 'text', content: 'Hello!' },
    { type: 'done' },
  ],
})

Pass a function to make responses request-aware, or pass an array of arrays to return different chunks on each call (sequenced mode). Use the optional history array to capture every request for assertions.

recordingAdapter + inMemorySink — capture real calls

import { recordingAdapter, inMemorySink, anthropic } from '@agentskit/adapters'

const sink = inMemorySink()
const adapter = recordingAdapter(
  anthropic({ apiKey: process.env.ANTHROPIC_API_KEY!, model: 'claude-sonnet-4-6' }),
  sink,
)
// Runs the real LLM and captures every chunk to sink.fixture

replayAdapter — replay captured fixtures

import { replayAdapter } from '@agentskit/adapters'
import fixture from './fixture.json'

const adapter = replayAdapter(fixture) // no network calls

Typical workflow: record once in dev → commit JSON fixture → replay in CI.

Contributors

License

MIT — see LICENSE.

Docs

Full documentation · GitHub

Maturity and compatibility

• Stability: beta — see docs/STABILITY.md
• The implementation is hardened for a future freeze, but promotion still requires the 90-day beta window, two released minor lines, accepted package RFC, and repository evidence required by ADR 0024.
• Node.js 20+ and TypeScript strict mode
• Published as @agentskit/adapters

Contributing

See CONTRIBUTING.md and the monorepo LICENSE.