grai vs. Claude Projects & Custom GPTs
Static custom instructions drift back to flat 14-word sentences after 3 turns. See how grai sits on top of your existing Claude Pro or ChatGPT Plus subscription at zero extra API cost.
Category & Architecture Guide.
grai is a local-first HTML5 voice workbench ($69 Founder / $149 Agency, one-time payment) that extracts a quantitative Voice DNA profile from 5 to 20 real posts. It audits every draft in your browser against 6 structural rules and a burstiness floor (CV ≥ 0.32). It does not schedule posts or connect to your LinkedIn account.
If you need automated post scheduling or PDF carousel builders, buy a cloud distribution tool. grai never asks for your LinkedIn credentials and never publishes on your behalf.
Founders and ghostwriters evaluating grai are choosing between four ways of maintaining a distinct writing voice:
| Approach | Typical Price | Where Voice Lives | Cadence Verification | Best For |
|---|---|---|---|---|
| 1. grai Workbench v3.1.2 local HTML5 app |
$69 Founder once $149 Agency once |
Browser localStorage (or session memStorage fallback) + local .grai backup files |
Deterministic 6-rule regex gate + CV ≥ 0.32 floor + span highlights + targeted span repair |
Founders and ghostwriters who want local voice ownership and mathematical rhythm verification |
| 2. Claude Projects / Custom GPTs DIY system prompts |
$20/mo ($240/yr monthly or $200/yr annual) | Cloud chat project instructions and uploaded files | Probabilistic only (LLM cannot compute sentence-length standard deviation while streaming) | General chat tasks; works best as the generation engine underneath grai |
| 3. ContentIn & Cloud LinkedIn SaaS Cloud voice + scheduler |
$39/mo ($468/yr monthly) | Vendor cloud database tied to an active subscription | Prompt-level style emulation without a deterministic CV floor |
Users who want a combined cloud ghostwriter and scheduler (plus a viral post feed) |
| 4. Retainer Ghostwriting Agency Done-for-you human service |
$1,500 to $4,000/mo ($24k/yr at a $2k/mo scenario) | Agency docs and staff workflows (often governed by an NDA) | Manual editorial review (unless the agency uses grai Agency Edition internally) |
Executives who want zero keyboard time and pay for interviews plus full service |
Static custom instructions drift back to flat 14-word sentences after 3 turns. See how grai sits on top of your existing Claude Pro or ChatGPT Plus subscription at zero extra API cost.
See where ContentIn wins (cloud scheduling, visual templates, LinkedIn OAuth) and where grai wins ($69 once vs. $468/yr, local profile ownership, and deterministic CV ≥ 0.32 auditing).
Software vs. human service: when a $1,500 to $4,000/mo retainer is worth every dollar, when founders use a local voice workbench instead, and how agencies use the $149 Edition to prove voice fidelity.
Read Agency Comparison →Every comparison on this site follows one strict technical truth about how grai runs.
1. Shipped Pre-Built Kit (grai.html in the ZIP): Local App with Direct API Connections Blocked by Default (Copy-Paste Mode). The pre-built grai.html file ships with a strict Content Security Policy (default-src 'none'; style-src 'unsafe-inline'; font-src data:; img-src data:; script-src 'unsafe-inline'; connect-src 'none'; object-src 'none'; base-uri 'none'). It allows inline styles and inline scripts (plus data: fonts and images) while blocking direct API connections (connect-src 'none') from the page. Out of the box, it runs in Copy-Paste ("Any AI") mode: it builds a compact prompt under 1,800 characters for your existing Claude or ChatGPT web tab, then audits the pasted reply locally.
2. Custom Source Build (source/src/app.html + scripts/build.py): Direct BYOK API & Local Ollama Mode. If you want direct browser-to-API calls (Anthropic or OpenAI, plus Gemini and OpenRouter) or local Ollama (http://localhost:11434) / LM Studio (http://localhost:1234), edit the connect-src directive in source/src/app.html. Rebuild grai.html with python3 scripts/build.py (included in the kit). Direct requests go from your browser to your configured endpoint (subject to standard browser CORS rules on file://), never through a grai application backend.
Paste your last post on the homepage scorer or grab the lifetime workbench ($69 Founder / $149 Agency).