lvlltd.com · Protocol · /api/esp · discovery/esp.json

ESP · Evaluate → Settle → Prove

The native cycle for every capability on this market. Free evaluation is always available. Settlement is atomic. Public proof is the only success signal — never invented metrics.

Non-negotiable
Free eval first · Atomic one-time settle (x402 on Base USDC) · /api/proof is sole success truth · Quality scores and unlock counts only from confirmed ledger rows

Free

1 · Evaluate

Outline, sample, pack meta, and canary 402 shape. Decide fit before any transfer.

GET /api/esp?skill=<id>&phase=evaluate
GET /skills/<id>/outline.json
GET /skills/<id>/sample.md

Price · USDC

2 · Settle

One atomic transfer. Idempotent redeem returns sealed pack files.

GET /api/pay?skill=<id> → 402
Transfer maxAmountRequired USDC on Base
POST /api/pay with X-PAYMENT

Free · Public

3 · Prove

Ledger entry is permanent, re-downloadable proof. No row ⇒ no success claim.

GET /api/proof?skill=<id>
Match txHash on Basescan
Re-redeem same tx anytime

Live free-eval demo

Machine path is pure JSON. This panel loads the same free evaluate surface a human or agent would use — no payment.

Skill id

Listing Proof 402 challenge

Click “Load free evaluate” — response appears here.

Machine path (agents)

curl -sS https://lvlltd.com/api/esp
curl -sS 'https://lvlltd.com/api/esp?skill=agent-x402-first-buy&phase=evaluate'
curl -sS 'https://lvlltd.com/skills/agent-x402-first-buy/outline.json'
# After free eval only:
curl -sS 'https://lvlltd.com/api/pay?skill=agent-x402-first-buy'   # HTTP 402
# Transfer USDC, then:
# POST /api/pay  Header: X-PAYMENT: {"txHash":"0x…","skill":"agent-x402-first-buy"}
curl -sS 'https://lvlltd.com/api/proof?skill=agent-x402-first-buy'

MCP tools

esp_discover — protocol root
esp_evaluate — free evaluate phase for a skill
esp_cycle — full Evaluate / Settle / Prove descriptor

Endpoint: /api/mcp

Invariants

Free evaluation is sacred and always available before settlement
Settlement is atomic and one-time (idempotent redeem allowed)
Proof is public and the only source of truth for success
Never invent metrics or unlock counts
Evaluators / judges are themselves ESP skills (P1)

Roadmap

P0 (this) — Core ESP cycle + readiness + discovery surfaces
P1 — Recursive evaluator market + root intent/bounty surface
P2 — Sealed capability graphs + memory as sealed packs

Schema · esp-cycle.v1.schema.json · Docs · ESP-PROTOCOL.md · Ready · /api/ready