# Apertis Changelog: 2.2.18 — Feature Added

Canonical page: https://apertis.ai/changelog/2.2.18
Markdown mirror: https://apertis.ai/changelog/2.2.18.md
Version: 2.2.18
Title: Feature Added
Published: 2026-03-01
Category: feature

✨ New Feature: Context Compression

## Details

Context Compression automatically summarizes conversation history using a smaller, cost-efficient model before sending requests to your primary model. This significantly reduces input token costs while preserving conversation context.

  ### Highlights

  - **Up to 78% token savings** on long multi-turn conversations
  - **Three compression strategies** to balance quality vs. savings:
    - `conservative` — compresses after 8+ turns (minimal context loss)
    - `on` — compresses after 6+ turns (balanced)
    - `aggressive` — compresses after 3+ turns (maximum savings)
  - **All endpoints supported:**
    - `POST /v1/chat/completions`
    - `POST /v1/messages`
    - `POST /v1/responses`

  ### How to Enable

  #### Option 1: API Key Dashboard (Zero Code Changes)

  Go to [API Key Management](https://apertis.ai/token) → Edit your API key →
  Enable Context Compression and select your preferred strategy. All requests using
  that key will automatically apply compression.

  #### Option 2: Per-Request via Request Body

  ```json
  {
    "model": "gpt-4.1",
    "messages": [...],
    "compression": {
      "enabled": true,
      "strategy": "on",
      "model": "gpt-4.1-mini"
    }
  }
  ```

  #### Option 3: Per-Request via HTTP Headers

  X-Context-Compression: on
  X-Compression-Model: gpt-4.1-mini

  #### SDK Support

  Compression examples are now available for all supported SDKs:

  - Python SDK (OpenAI, Anthropic, Responses API)
  - TypeScript / Vercel AI SDK (@apertis/ai-sdk-provider)
  - LangChain (via default_headers)
  - LlamaIndex (via additional_kwargs)
  - LiteLLM (via extra_headers)

  #### Priority

  Request body params \> HTTP headers \> API key defaults.
  Per-request settings always override key-level defaults.

  See more on [**Documentation**](https://docs.apertis.ai/api/text-generation/context-compression)