π¦ i04 dragonfly: chameleon, faster, more careful, remembering its bestΒΆ
π¦ archived 2026-09-25, v2.17.0 Β· smoke test only Β· its ingredients were tested one at a time in echidna, its belief and caution returned in hippogriff
Question. Chameleon, but fast enough to run, exploring by a guided random walk with momentum, cautious where it is unsure ("worst case until proven otherwise"), and remembering the best it has seen.
Answer. About 5Γ faster, and it learned faster than chameleon early on, then degraded; two of its parts turned out not to work as designed. Paused in favour of testing its ingredients one at a time (echidna); its belief-and-caution ideas returned in hippogriff.
Design (agents/dragonfly.py), what differs from chameleonΒΆ
- History as leaky integrators: exponential traces of \([z_t, z_t - z_{t-1}, a_{t-1}, r_{t-1}]\) at
decays 0.5, 0.9, 0.99 (momenta of the latent). A linear recurrence, trained with
associative_scan, parallel over time, instead of backpropagation through a GRU. - Exploration is an Ornstein-Uhlenbeck walk per latent dimension, every step: \(\xi_d \leftarrow \rho_d \xi_d + \sqrt{1-\rho_d^2}\,\sigma_d \eta\), \(\rho_d = e^{-1/\tau_d}\). Its spread is \(\sigma_d\) whatever \(\rho_d\) (constant entropy) while it carries \(-\tfrac12\log(1-\rho_d^2)\) nats of momentum from step to step; \(\tau_d\) is how many steps a heading persists.
- A learned guide sets \(\tau_d, \sigma_d\) and Ξ΅ from the history, the measured entropy of each latent dimension, a pessimistic value, and p, the current performance relative to a golden cache.
- Pessimism: Q and V are ensembles (4 heads on bootstrap masks); the search scores candidates by alignment plus the ensemble's lower bound, so likely-bad candidates are vetoed.
- Golden cache: the best experiences by reward and by return, at most one per latent ball (canonical), with self-imitation of their actions.
Smoke test (330k steps)ΒΆ
| Time per update | 10.7 s on a quiet machine (chameleon: 47 s, loaded) |
| Episodes ending early | 49 % β 1 % by 140k steps, then back to 12-22 % |
| Mean reward per step | β9.4 β +0.41 (best) β β1.8 at the end |
| Candidates vetoed by the lower bound | 15-40 % |
| Deterministic test episode, last evals | overshoots at once (return β20) |
OutcomeΒΆ
- The cache position p saturated at 0. The cache holds only golden examples, so even its worst entry is excellent and every ordinary state falls below it; the guide never got a signal from p.
- The guide never moved: Ο, Ο, Ξ΅ stayed at their initial midpoints (32.5, 0.5, 0.5), so the question of how Ο relates to p or to the measured entropy was never answered.
- The veto was the part that visibly helped early on, which is why pessimism returned in echidna (tested alone) and hippogriff (as a safety check on a belief).
Records: results/i04_dragonfly/ (smoke-test progress and summary).