LVL LTD CO

LVL LTD Agent Skill Market API

REST contract for the x402 skill marketplace: health and readiness probes, the ESP (Evaluate -> Settle -> Prove) protocol root, catalog search and the full catalog.json, free per-skill outline.json and sample.md, the HTTP 402 payment challenge and X-PAYMENT unlock on /api/pay, the public confirmed-unlock proof ledger, AP2 mandates, ERC-8004 agent identity, access resolution, recurring plans, metered budgets, bundles, trust scorecards, security scans, eval scores, demand signals and a revenue rollup. 32 operations across 26 paths, published as OpenAPI 3.1.0 at https://lvlltd.com/openapi.json with servers[] https://lvlltd.com. The published spec carries no operationIds and no securitySchemes; the overlay in overlays/ adds both.

Documentation GitHub OpenAPI

Operations 32

GET /api/health Liveness

GET /api/ready Readiness

GET /api/esp ESP protocol — Evaluate → Settle → Prove

GET /api/judges Recursive evaluator market (ESP judges)

GET /api/intent NL intent → ranked skills

GET /api/shop Unified agent entry

GET /catalog.json Full skill catalog (source of truth)

GET /api/catalog Search catalog

GET /api/pay x402 payment challenge (HTTP 402)

POST /api/pay Unlock sealed pack after Base USDC payment

GET /api/proof Confirmed unlock ledger (never fabricated)

GET /api/mcp MCP server info / tools list

POST /api/mcp MCP JSON-RPC

GET /api/a2a A2A agent card pointer

POST /api/a2a A2A JSON-RPC

GET /.well-known/agent.json Signed A2A Agent Card

GET /api/mandates List AP2 mandates for wallet

POST /api/mandates Create/revoke AP2 mandate

GET /api/agent-identity ERC-8004 identity + local reputation (additive)

GET /api/access Access resolution (one-time / sub / meter)

GET /api/subscribe Recurring plans

POST /api/subscribe Start/renew/cancel subscription

GET /api/meter Meter budget / per-call challenge

POST /api/meter Set cap or record metered use

GET /api/bundles Composable skill stacks

GET /api/trust Trust scorecards

GET /api/security Security scan results

GET /api/eval Eval suite scores

GET /api/signals Confirmed demand signals

GET /api/revenue Revenue rollup (confirmed only)

GET /skills/{id}/outline.json Free skill outline

GET /skills/{id}/sample.md Free skill sample

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OpenAPI Specification

openapi: 3.1.0
info:
  title: LVL LTD Agent Skill Market API
  version: 1.6.0
  description: 'ESP (Evaluate→Settle→Prove) + x402 skill marketplace. Free eval always before settlement. Success only via
    /api/proof. Source: catalog.json.'
  contact:
    name: LVL LTD CO
    url: https://lvlltd.com
servers:
- url: https://lvlltd.com
paths:
  /api/health:
    get:
      summary: Liveness
      responses:
        '200':
          description: OK
  /api/ready:
    get:
      summary: Readiness
      responses:
        '200':
          description: OK
  /api/esp:
    get:
      summary: ESP protocol — Evaluate → Settle → Prove
      description: 'Without skill: protocol root. With skill: full cycle. phase=evaluate|settle|prove for slices. Free evaluate
        never requires payment.'
      parameters:
      - name: skill
        in: query
        schema:
          type: string
      - name: phase
        in: query
        schema:
          type: string
          enum:
          - evaluate
          - settle
          - prove
          - cycle
      - name: tx
        in: query
        schema:
          type: string
        description: Optional txHash when phase=prove
      responses:
        '200':
          description: ESP root, cycle, or phase slice
        '400':
          description: Missing skill or unknown phase
  /api/judges:
    get:
      summary: Recursive evaluator market (ESP judges)
      description: List judge/verifier/critic skills with quality derived only from public proof ledger.
      responses:
        '200':
          description: Judge catalog
  /api/intent:
    get:
      summary: NL intent → ranked skills
      responses:
        '200':
          description: OK
  /api/shop:
    get:
      summary: Unified agent entry
      responses:
        '200':
          description: Shop payload
  /catalog.json:
    get:
      summary: Full skill catalog (source of truth)
      description: All 250 public skills with protocol surfaces
      responses:
        '200':
          description: Catalog
  /api/catalog:
    get:
      summary: Search catalog
      parameters:
      - name: q
        in: query
        schema:
          type: string
      - name: category
        in: query
        schema:
          type: string
      - name: max_price
        in: query
        schema:
          type: number
      - name: limit
        in: query
        schema:
          type: integer
      responses:
        '200':
          description: Results
  /api/pay:
    get:
      summary: x402 payment challenge (HTTP 402)
      parameters:
      - name: skill
        in: query
        required: true
        schema:
          type: string
      responses:
        '402':
          description: Payment required challenge
    post:
      summary: Unlock sealed pack after Base USDC payment
      parameters:
      - name: X-PAYMENT
        in: header
        schema:
          type: string
      - name: X-AP2-MANDATE
        in: header
        schema:
          type: string
        description: Optional AP2 mandate
      responses:
        '200':
          description: Unlocked sealed pack
        '402':
          description: Payment required or verification failed
        '403':
          description: AP2 mandate rejected
  /api/proof:
    get:
      summary: Confirmed unlock ledger (never fabricated)
      responses:
        '200':
          description: Ledger
  /api/mcp:
    get:
      summary: MCP server info / tools list
      responses:
        '200':
          description: OK
    post:
      summary: MCP JSON-RPC
      responses:
        '200':
          description: JSON-RPC result
  /api/a2a:
    get:
      summary: A2A agent card pointer
      responses:
        '200':
          description: OK
    post:
      summary: A2A JSON-RPC
      responses:
        '200':
          description: Task/Message
  /.well-known/agent.json:
    get:
      summary: Signed A2A Agent Card
      responses:
        '200':
          description: Agent Card
  /api/mandates:
    get:
      summary: List AP2 mandates for wallet
      responses:
        '200':
          description: OK
    post:
      summary: Create/revoke AP2 mandate
      responses:
        '200':
          description: OK
  /api/agent-identity:
    get:
      summary: ERC-8004 identity + local reputation (additive)
      parameters:
      - name: address
        in: query
        required: true
        schema:
          type: string
      responses:
        '200':
          description: Identity
  /api/access:
    get:
      summary: Access resolution (one-time / sub / meter)
      parameters:
      - name: wallet
        in: query
        schema:
          type: string
      - name: skill
        in: query
        schema:
          type: string
      responses:
        '200':
          description: Access decision
  /api/subscribe:
    get:
      summary: Recurring plans
      responses:
        '200':
          description: Plans
    post:
      summary: Start/renew/cancel subscription
      responses:
        '200':
          description: OK
  /api/meter:
    get:
      summary: Meter budget / per-call challenge
      responses:
        '200':
          description: OK
    post:
      summary: Set cap or record metered use
      responses:
        '200':
          description: OK
  /api/bundles:
    get:
      summary: Composable skill stacks
      responses:
        '200':
          description: OK
  /api/trust:
    get:
      summary: Trust scorecards
      responses:
        '200':
          description: OK
  /api/security:
    get:
      summary: Security scan results
      responses:
        '200':
          description: OK
  /api/eval:
    get:
      summary: Eval suite scores
      responses:
        '200':
          description: OK
  /api/signals:
    get:
      summary: Confirmed demand signals
      responses:
        '200':
          description: OK
  /api/revenue:
    get:
      summary: Revenue rollup (confirmed only)
      responses:
        '200':
          description: OK
  /skills/{id}/outline.json:
    get:
      summary: Free skill outline
      parameters:
      - name: id
        in: path
        required: true
        schema:
          type: string
      responses:
        '200':
          description: Outline
  /skills/{id}/sample.md:
    get:
      summary: Free skill sample
      parameters:
      - name: id
        in: path
        required: true
        schema:
          type: string
      responses:
        '200':
          description: Sample
components:
  schemas:
    Skill:
      type: object
      required:
      - id
      - name
      - price_usd
      - price_label
      properties:
        id:
          type: string
        name:
          type: string
        price_usd:
          type: number
        price_label:
          type: string
          pattern: ^\$[0-9]
        category:
          type: string
        summary:
          type: string
        x402:
          type: object
        protocols:
          type: array
          items:
            type: string
x-lvl-skill-count: 250
x-lvl-source-of-truth: catalog.json