Coding Evaluation Differences: Sol vs. Fable
ZainHasan6 · x · 2026-07-15
This post compares the capabilities of two coding/agent configurations, Sol and Fable. The core conclusion is that they "solve different problems," with a correlation of only 0.48.
Key Results
- Both solved 88 tasks under optimal configurations
- Solved only by Sol: 9 tasks
- Solved only by Fable: 12 tasks
- Solved by neither: 4 tasks
Different Failure Modes
- When Sol fails, there is a 20% chance it breaks existing tests in the repo
- When Fable fails, it's more commonly a "near miss," with about 65% of cases missing the final new test
Stability and Limits
- Across 26 previous configurations, no model exceeded 80% reliability (the ratio of passing the same task 4/4 times)
- Sol's peak reliability is 84.3%, with 61 tasks achieving a 4/4 pass rate
- Fable has a higher peak at 88%, beating Sol's 85.8%
- However, Sol is described as a "more reliable tool," while Fable is more likely to produce occasional but spectacular results
Related event: Sol vs Fable: Coding Agent Benchmarks Show Specialization, Not Dominance(9 posts)→
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