OpenCode + Free AI Models: What You Can Really Do Without Paying

What is OpenCode and Who Built It

OpenCode is an open-source AI coding agent created by Anomaly. It started as a terminal tool and quickly grew into one of the most important players in the AI coding ecosystem.

Numbers that speak for themselves:

• 163,000 stars on GitHub
• 900+ contributors worldwide
• 13,148 commits in the repository
• 7.5 million developers use it monthly
• 19,200 forks — an active community builds tools on top of it

The project is available under the MIT license — use, modify, and distribute freely. Available as a terminal tool, desktop app (beta on macOS, Windows, Linux), and IDE extension.

What You Can Do with OpenCode and Free Models — Concrete Use Cases

OpenCode isn't "just another AI assistant." It's a full agent that understands your repository, edits files, runs commands, and coordinates multi-step tasks. Paired with free models via OpenRouter or OpenCode Go, it delivers real capabilities:

1. Code Refactoring and Cleanup

Feed your entire project into context (up to 1M tokens with Qwen 3.6 Plus) and ask for:

• Converting class components to React hooks
• Refactoring repetitive code into utility functions
• Migrating from CommonJS to ESM
• Removing dead code

2. Code Review and Security Analysis

The plan agent in OpenCode is read-only — perfect for audits:

• Reviews pull requests and suggests fixes
• Searches for potential security vulnerabilities
• Analyzes dependencies for known CVEs
• Checks architectural consistency

3. Code Generation from Natural Language

Describe what you want — OpenCode creates files, runs tests, fixes errors:

• UI components with Tailwind CSS
• API endpoints in Next.js
• Automation scripts (CI/CD, deploy)
• Unit and integration tests

4. Exploring Unfamiliar Repositories

New project on the team? OpenCode with the plan agent reads the entire structure, explains the architecture, and points to key files — with zero risk of accidental modification.

5. Automating Repetitive Tasks

• Generating documentation from code
• Migrating types in TypeScript
• Batch renaming variables
• Converting data formats

Free Options — What Works Today vs What Ended

OpenRouter — Free Preview (Works)

OpenRouter is an AI model aggregator with 25+ free models and 4 free providers. The free plan gives you 50 requests per day and 20 requests per minute.

Qwen 3.6 Plus is available free as qwen/qwen3.6-plus:free — 1M context window, hybrid linear attention + MoE architecture.

Important: OpenRouter does not train on your data. Provider-side retention can be disabled at the account level. This is a key difference vs direct API from Alibaba, which collects prompts to improve the model.

OpenCode Go — $5 First Month, Then $10/Month (Works)

Subscription from OpenCode creators. Included:

• GLM-5.1, GLM-5 — models from Zhipu AI
• Kimi K2.5, Kimi K2.6 — models from Moonshot AI
• MiMo-V2.5-Pro, MiMo-V2.5 — models from Xiaomi
• Qwen3.5 Plus, Qwen3.6 Plus — flagship models from Alibaba
• MiniMax M2.5, MiniMax M2.7 — models from MiniMax
• DeepSeek V4 Pro, DeepSeek V4 Flash — models from DeepSeek

Limit: requests counted per 5-hour window. For example, Qwen 3.6 Plus has a limit of 3,400 requests per 5 hours.

What Ended

• Qwen OAuth free tier — discontinued April 15, 2026 (was 1,000 requests/day, then 100)
• Qwen 3.6 Plus Free in OpenCode Zen — deprecated April 8, 2026
• Community plugins (opencode-qwen-auth, opencode-qwen-oauth) — may no longer work after OAuth discontinuation

OpenCode Go vs OpenRouter vs Paid Solutions — Honest Comparison

When Free Options Are Enough

• Experiments and learning — OpenRouter free (50 req/day) to start
• Small projects and side-projects — OpenCode Go at $10/mo (~40 PLN)
• Prototyping and proof-of-concept — Qwen 3.6 Plus with 1M context fits entire repositories

When to Pay for Claude Pro / ChatGPT Plus

• Production with confidential data — paid plans offer better data control
• Complex tasks requiring highest quality — Claude Opus 4.5 is slightly better on SWE-bench Pro
• Teams needing collaboration features — paid plans have admin controls, SSO, SLA

Benchmarks — Do Free Models Really Compete with Paid Ones

Qwen 3.6 Plus (free on OpenRouter) vs Claude Opus 4.5 (paid, $15/$75 per 1M tokens):

Conclusion: In agentic terminal coding, Qwen 3.6 Plus is better than Claude Opus 4.5. In complex engineering tasks — Claude wins slightly. Differences are marginal (under 3 percentage points).

How to Configure OpenCode + Free Models — Step by Step

Step 1: Install OpenCode

# npm (simplest)
npm install -g opencode-ai

# or curl (YOLO install)
curl -fsSL https://opencode.ai/install | bash

# macOS Homebrew (recommended)
brew install anomalyco/tap/opencode

# Windows Scoop
scoop install opencode

Step 2: Option A — OpenRouter (Free)

1. Create an account at openrouter.ai
2. Generate an API key in settings
3. Configure the provider in opencode.json:

{
  "$schema": "https://opencode.ai/config.json",
  "provider": {
    "openrouter": {
      "npm": "@ai-sdk/openai-compatible",
      "options": {
        "baseURL": "https://openrouter.ai/api/v1",
        "apiKey": "sk-or-v1-..."
      },
      "models": {
        "qwen3.6-plus-free": {
          "name": "Qwen 3.6 Plus (free)",
          "id": "qwen/qwen3.6-plus:free",
          "limit": {
            "context": 1000000,
            "output": 65536
          }
        }
      }
    }
  }
}

Step 3: Option B — OpenCode Go ($10/mo)

1. Create an account at opencode.ai/go
2. Subscribe for $5 (first month)
3. Configure the custom provider:

{
  "$schema": "https://opencode.ai/config.json",
  "provider": {
    "custom": {
      "npm": "@ai-sdk/openai-compatible",
      "options": {
        "baseURL": "https://opencode.ai/zen/go/v1",
        "apiKey": "your-key"
      },
      "models": {
        "qwen3.6-plus": {
          "name": "qwen3.6-plus"
        }
      }
    }
  }
}

Step 4: Launch and Select the Model

opencode

Type /models, search for your provider, and select the model.

What You Gain vs What You Lose

Gains

• Near-zero cost — OpenRouter free (50 req/day) or OpenCode Go at ~40 PLN/mo
• Full coding agent — not a chatbot, but an agent with file, terminal, and repo access
• 1M context window — fits entire repositories in one context
• Open source — no vendor lock-in, full transparency
• Privacy-first — OpenCode doesn't store your code; OpenRouter doesn't train on data
• 75+ providers — connect any model, including local ones

Limitations

• Rate limits — OpenRouter free is 50 requests/day; not enough for larger projects
• Edge quality — Qwen 3.6 Plus is great, but Claude Opus 4.5 still leads on SWE-bench Pro
• No open-weight — Qwen 3.6 Plus is API-only; can't run locally
• Preview data collection — if using direct Alibaba API (not via OpenRouter), the model collects prompts

What You Can Implement Today

1. Install OpenCode — one command, 2 minutes
2. Create an OpenRouter account — free, 50 requests/day to start
3. Connect Qwen 3.6 Plus — 1M context window, free, #1 on Terminal-Bench
4. Test on your repository — feed all your code and see how the agent handles your project
5. Compare with paid options — same tasks, different models, objective evaluation
6. Consider OpenCode Go — if 50 requests/day isn't enough, $10/mo (~40 PLN) gives ~2,000+ requests

How Much You Can Gain

Time: Qwen 3.6 Plus is 65% faster than Qwen 3.5 Plus. At 50 requests/day, that's ~20 minutes saved waiting.

Cost: OpenCode Go at $10/month (~40 PLN) vs Claude Pro at $20/month (~80 PLN) — half the price for access to a model that beats Claude on Terminal-Bench.

Quality: #1 on Terminal-Bench (61.6%), top 3 on SWE-bench Verified (78.8%). This isn't a "cheap alternative" — it's a competitor to the leaders.

For Polish SMBs: 40 PLN monthly for a tool that can refactor code, find bugs, generate components, and understand entire repositories — an investment that pays back in one saved developer day.

Comparison: Claude Opus 4.5 via API costs $15 per million input tokens + $75 per output. For a typical project of 500K input + 100K output = ~$15. OpenCode Go at $10/month gives you the same without counting tokens.

Important: If testing via OpenRouter, remember — OpenRouter doesn't train on your data. If using direct Alibaba API, the model collects prompts and responses to improve itself. For production with confidential data, use OpenCode Go or OpenRouter with provider retention disabled.