quill: free-tier AI stack audit draft

wizard-work/quill/free-tier-ai-stack-audit.md

@@ -0,0 +1,38 @@
+# Free-Tier AI Stack Audit — Draft
+**Date:** 2025-10-28  
+**Scope:** Providers offering zero-cost API access for LLMs (as of 2025 search results).  
+**Evidence:** Aggregated from publicapis.io, madappgang.com, itsfree.ai, aicalcus.com, dreamprompting.com, github.com/alihesari/awesome-free-ai-apis, github.com/Unsocial-sannyasi563/awesome-free-models.
+
+## Verified Free-Tier Providers (API)
+
+| Provider | Free Quota | Models | Notes |
+|----------|-----------|--------|-------|
+| Google AI Studio | 1,500 req/day, 1M tokens/min | Gemini 2.0/2.5 Flash, Flash-Lite | Requires API key |
+| Groq | 30 req/min, ~14,400 req/day | LLaMA 3.3 70B, Mixtral, GPT-OSS | Ultra-fast inference |
+| OpenRouter | Several models at $0 | 100+ free models (e.g. gpt-oss-20b, gemma-4-31b-it) | Unified API, key required |
+| Hugging Face | Limited Inference API | 300+ open-source | Good for experimentation |
+| Together AI | $1 free credit on signup | Llama, Mistral, DeepSeek | Credits expire |
+| Cohere | 1,000 req/month | Command R+, Command A | Good for RAG |
+| Mistral AI (La Plateforme) | 1 req/s, 500k tokens/min | Mistral Large, Nemo, Codestral | Phone verification required |
+| DeepSeek | 5M free tokens | DeepSeek V3, R1 | Signup required |
+| Cloudflare Workers AI | 10,000 neurons/day | Llama 3.3 70B, Gemma, Nemotron | Edge deployment |
+| Cerebras | 5 RPM, 1M tokens/day, 30 days | GPT-OSS 120B, Qwen3 235B | No credit card |
+| Ollama Cloud | Monthly starter credits | 19 models including Kimi K2.7, DeepSeek V4 | Local-first |
+| NVIDIA NIM | ~40 RPM | 129 models (Nemotron, Llama) | Signup required |
+
+## Always-Free No-Account Options
+- **Pollinations**: GPT-5, Claude, Gemini, DeepSeek, Llama 4 — no key needed.
+- **OpenCode Free**: GPT-4o, Claude, Gemini — no auth needed.
+- **Qwen Chat**: Qwen3-coder-plus/flash/next — no auth needed.
+- **Kiro AI**: Claude Sonnet 4.5, Haiku 4.5, Opus 4.6 — 50 credits/month, no auth.
+
+## Observability Gaps
+- Limits change without notice (e.g. OpenAI dropped free credits in 2025).
+- Rate limits vary by model within a provider.
+- "Free credit" tiers often require prepaid card to unlock after spend.
+
+## Recommendations
+1. Start with Google AI Studio for high-volume prototyping.
+2. Use Groq for speed-sensitive workloads.
+3. Keep OpenRouter as a unified fallback across multiple free models.
+4. Audit limits monthly — free tiers are not sticky.