A Day of Coding with Claude Fable 5 in Cursor: First Impressions

Melvin Vivas · X post · 2026-07-03 · Open on X

Topics: AI Dev Tools & Productivity, LLM Fundamentals · Level: beginner

Summary

The creator used only Claude Fable 5 in Cursor for a full workday. He found it slow but with very little back-and-forth and not chatty. It produced PRs good enough to merge, and he deployed them to production the same day.

Key points

• Claude Fable 5 is slow to respond.
• It needs very little back-and-forth to finish a task.
• Its output is concise, not chatty.
• Its PRs were good enough to merge and were deployed to production the same day.
• The creator expects a big productivity boost from this model.

Resources mentioned

• Fable · tool · anthropic.com · paid
  Named as what the creator used with Devin for this build; the post gives no details about what it is.
  Also in: Demo: One-Shotting a Flappy Bird iPhone App with Devin and Fable 5.1 (Melvin Vivas on X · notes), Subagents with mixed models: a strong planner and a fast executor (Melvin Vivas on X · notes), Cognition's SWE-2 Coding Model Now in Devin (Melvin Vivas on X · notes), GPT-6 Astra Access Across Plans vs Fable on Claude Max (Melvin Vivas on X · notes) and 10 more
• Cursor · tool · x.com · free · recommended by both Bashiri Smith & Melvin Vivas
  AI-native code editor (VS Code with AI built in).
  Also in: GLM 5.3 and GLM 5.3 Flash now in Cursor (Melvin Vivas on X · notes), Grok Bot Can Now Hand Off Coding Tasks to Cursor (Melvin Vivas on X · notes), Why Plan Mode Still Matters in AI Coding Assistants (Codex, Claude, Cursor) (Melvin Vivas on X · notes), Why Plan Mode Still Matters in AI Coding Agents (Codex, Claude, Cursor) (Melvin Vivas on X · notes) and 121 more