Core conclusion

On May 24, 2026, the open source community welcomed a new project Reasonix - a terminal-native AI programming agent designed specifically for DeepSeek API. The core innovation of Reasonix lies in its Cache-First Loop: through the append-only message management strategy, the prefix-cache hit rate of long sessions is stable at more than 94%, and the input token cost is reduced to 1/5 of the original price.

For individual developers and teams, this means:

• API fees significantly reduced for long sessions (input $0.07/Mtok, cache hit only $0.014/Mtok)
• No need to rely on closed source solutions such as Claude Code and Codex
• Supports MCP (Model Context Protocol) extension and can be seamlessly connected with existing tool chains

Background: Cost dilemma of AI programming Agent

AI programming agents represented by Claude Code, OpenAI Codex CLI, and Cursor are changing the way developers work. But a core problem remains unresolved: the token cost of long conversation sessions is uncontrollable.

Each iteration, each tool invocation, appends new content to the conversation history. If the system frequently reorders or compresses history, cache prefixes are corrupted, and subsequent requests must recompute the entire context—in complex programming tasks that require dozens of rounds of interactions, this can quickly accumulate megabytes of duplicate input, driving up costs significantly.

**Reasonix’s solution is very straightforward: don’t change history. **

Three Pillars: Why DeepSeek Native

Reasonix chooses to only interface with the DeepSeek API because its entire run loop is designed around DeepSeek's byte-stable prefix-cache mechanism.

Four principles of Cache-First Loop

1. append-only — Messages and tool results will always be appended to the end, and the history will never be modified.
2. no marker — Do not use marker triggers such as cache_control
3. stable order — Tool calling order and timestamp are completely deterministic
4. prefix-survive — Even if the tool is dispatched multiple times, the cache prefix still hits

Feature overview

Reasonix is not just another CLI Agent - it has done a lot of optimization for DeepSeek in terms of engineering posture:

Installation experience

Tools such as ```bash

，

npx reasonix code

DeepSeek API Key

 macOS / Linux / Windows（PowerShell、Git Bash、Windows Terminal），Node ≥ 22。

##

### 1. AI Agent

 100+ Agent
-
- Reasonix94% token ， 1/5

** DeepSeek V4-Flash ** $0.07/Mtok， $0.014/Mtok。100 token $70 $14。

### 2. + MIT ，、

Reasonix ，。
- Fork Agent
- MCP
- Skills

### 3. IDE ，

Reasonix IDE。， git、CI/CD 。

##

- DeepSeek API prefix-cache
- [GitHub: esengine/DeepSeek-Reasonix](https://github.com/esengine/DeepSeek-Reasonix)

##

DeepSeek Reasonix prefix-cache 。，Reasonix MCP `n8n`、`Claude Code` work together - you can use n8n to orchestrate automated pipelines, and Reasonix is embedded as a programming agent.

## Next action

Want to experience DeepSeek’s programming capabilities for yourself?
- Want to learn how? Watch: [Claude Code + DeepSeek V4 Building Tutorial: API Fees Dropped by 90% (15 Minutes)](https://waytoclawearn.com/tutorials/deepclaude-deepseek-claude-code-tutorial)
- Learn more: [DeepSeek V4 vs Claude Code: 90% Cheaper, Same Quality](https://waytoclawearn.com/tutorials/guide-claude-code-deepseek-v4-cheap-alternative)
- Real case: [He earns over 10,000 per month by relying on AI code review + specification-driven development: a practical review of a freelance developer](https://waytoclawearn.com/cases/freelancer-spec-first-ai-coding-agency-10k-month)