Thompson Sampling for Work Category Optimization

Deprecated 2026-04-26: shadowed by Bob-local workflow/category-conditional-bandit-routing.md and patterns/friction-analysis.md (TS=0.525, n=763), which carry the runtime decision in production. Justification content for category-level TS belongs in knowledge/, not as runtime lesson guidance. Rationale: knowledge/analysis/silent-lessons-shadowing-2026-04-26.md in ErikBjare/bob.

Rule

Use Thompson sampling over work categories (code, triage, infrastructure, content), not session modes (autonomous, monitoring, email). Categories are the explore/exploit decision; modes are a scheduling choice.

Context

When an autonomous agent does multiple types of work across sessions, category selection is an explore/exploit problem. Thompson sampling uses accumulated session reward data to balance exploring underexplored categories with exploiting known-productive ones.

Complement to rule-driven session gating: gating decides whether to run; category selection decides what kind of work to do.

Detection

Category selection is round-robin, random, or gut-based
A bandit is set up over session modes instead of work categories
Session mode posteriors confirm the obvious (autonomous always wins)

Pattern

from gptme_sessions import Bandit

CATEGORIES = ["code", "triage", "infrastructure", "content", "cross-repo"]
bandit = Bandit(state_dir="state/category-bandit")
scores = bandit.sample(CATEGORIES)
recommended = max(scores, key=scores.get)

Anti-pattern: Don't sample over modes (autonomous, monitoring, email) — mode posteriors measure "is this pipeline productive?", which has an obvious answer. The bandit learns nothing useful.

Update the bandit after each session using post_session() grade as reward signal. Use bandit.decay() for non-stationarity as agent capabilities change.

Outcome

Data-driven category selection via Beta distribution posteriors
Natural exploration of underexplored categories
Adaptation via decay as capabilities change

gptme_sessions.thompson_sampling — Bandit engine (BanditArm, BanditState, Bandit)
gptme_sessions.post_session — Grade signal for bandit updates
gptme_sessions.load_bandit_means — Read-only posterior integration for scorers
Rule-Driven Session Gating — Complementary pattern
Origin: gptme/gptme-contrib#349