two-towers-routing

name	two-towers-routing
description	Use when implementing or tuning Maestro's Two-Towers persona↔skill matcher: deterministic scoring, ranking, tie-breaking, and fallback selection.

Two-Towers Routing Skill

Use When

• Selecting the best persona for a micro-project.
• Changing scoring, weighting, or the fallback policy of the matcher.

Concept

Two encoders produce embeddings — a persona tower and a skill/task tower. The matcher scores personas against the task and returns a ranked, reproducible selection.

Workflow

1. Keep the matcher in domain/application; embeddings come through an infrastructure port.
2. Score all candidates; sort stably with an explicit tie-breaker (never rely on map order).
3. Return a ranked list with scores + margin; log the pick and runner-up via tracing.
4. Apply a documented default persona when nothing clears the minimum threshold.
5. Keep thresholds/weights in named constants or config — no inline magic numbers.

Verification

• Determinism test: identical input → identical ranking.
• Tie-break and fallback tests.
• Baseline-vs-new ranking comparison on a fixed fixture set when scoring changes.

Outputs

• An auditable, deterministic routing decision with tests and (for scoring changes) a before/after ranking delta.