# Agentic Experience (AX)

Use this skill when designing, reviewing, or implementing systems whose primary user may be an AI agent, automation, tool-using model, or multi-agent team.

## Core Frame

Agentic Experience is the design discipline for systems whose primary user is an agent rather than a human.

The central failure mode is substrate debt: the accumulated cost of carrying interface assumptions from one kind of user into systems used by another.

For agents, protocol design becomes experience design:

- A schema is not backend plumbing. It is the interface.
- A manifest is not documentation. It is onboarding.
- Idempotency is not an implementation detail. It is the safety layer.
- Structured errors are not developer ergonomics. They are recoverability.
- Cost annotations are not observability. They are part of the decision surface.

## Review Flow

1. Start from the canonical manifest or init endpoint.
2. Identify every operation an agent can perform.
3. For each operation, inspect inputs, outputs, permissions, side effects, idempotency, freshness, and errors.
4. Check whether an agent can recover from missing data, stale state, and failed calls without guessing.
5. Report substrate debt as concrete interface assumptions, not as vague UX critique.

## Supporting Artifacts

- `/agentic-experience.md`
- `/ax-checklist.md`
- `/substrate-debt.md`