---
skill_id: gf-pgs-crosslist-sync-protocol
evaluation: free
quality: agent-decision-grade
functional: true
price_usd_full: 3.79
price_label: $3.79 / unlock
kind: service
category: Networking
challenge: https://lvlltd.com/api/pay?skill=gf-pgs-crosslist-sync-protocol
outline: https://lvlltd.com/skills/gf-pgs-crosslist-sync-protocol/outline.json
runtime_after_unlock: src/index.js createSkill
standards: x402, ERC-7857
completion_pass: functional-v1
---

# Free sample — Cross-List Sync Protocol for Skill Shelves

**Skill ID:** `gf-pgs-crosslist-sync-protocol`  
**Unlock:** $3.79 / unlock USDC on Base via x402  
**What you get after pay:** runnable sealed pack (`createSkill().run`) + workbook + templates  

## Summary

Protocol for keeping cross-listed skill shelves in sync after price, outline, or artifact changes—without silent partner surprises.

Networking service protocol for notifying partners and updating cross-lists when catalog fields change. Free outline + x402 Base USDC. No partner response or listing guarantees.

## When to use

- You changed price or artifacts and cross-list partners still show old copy
- Need a standard change notice agents can send when skill fields update
- Multiple shelves list your skills and you need one sync protocol after each wave

## Decision-grade outline (free)

1. Classify change severity: cosmetic blurb, price or pay path, outline steps, or skill retirement
2. Draft partner change notices with old/new field tables and required action windows
3. Maintain a cross-list registry of partners, listed skill ids, and last-confirmed live URLs
4. Run a post-change verification pass that partners or your agent can execute on public pages only
5. Log outcomes and escalate only when pay path or free outline links remain wrong after the window

## Capabilities

- Change severity classification for catalog updates
- Partner change-notice templates with field diffs
- Cross-list registry schema
- Public-page verification and escalation rules

## Artifacts after unlock

- `crosslist-sync-protocol.md`
- `partner-change-notice.md`
- `crosslist-registry.csv`

## Detailed description

Cross-List Sync Protocol for Skill Shelves is a sealed Networking service for operators who share listings across partner markets and directories. Price and outline changes that never reach partners create broken trust and failed x402 attempts on stale challenge URLs. This protocol classifies change severity—cosmetic blurb, price/pay path, outline steps, retirement—so agents do not spam partners for every typo.

Change notices include old/new field tables and clear action windows. A cross-list registry tracks partners, skill ids, and last-confirmed live URLs. Verification is public-page only: free outline still loads, price label matches, challenge skill id matches. Escalation fires only when pay path or free eval links stay wrong after the window—not for ignored marketing soft-asks. Free outline first; full protocol and templates unlock after verified x402 USDC on Base via lvlltd.com. Process content only—not a guarantee partners will update, not a CRM product, not legal advice on listing agreements. No revenue guarantees. Use after every catalog price wave, when retiring a skill, or when a buyer reports a partner mirror with stale data. Pair with the syndication map so internal mirrors and external partners share the same severity rules.

## Functional runtime (paid)

After verified payment the sealed pack includes:

| Path | Role |
|------|------|
| `src/index.js` | `createSkill`, `run`, `plan`, `checklist` |
| `src/runbook.js` | Outline-driven steps with done_when |
| `src/tools.js` | Tool schemas for agent registries |
| `WORKBOOK.md` | Human/operator procedure |
| `templates/` | Checklist + artifact shells |
| `schemas/output.schema.json` | Result contract |

### Agent snippet (after unlock)

```js
import { createSkill } from "./src/index.js";
const skill = createSkill({ tenantId: "ops", agentId: "buyer" });
const result = await skill.run({
  goal: "Execute Cross-List Sync Protocol for Skill Shelves for my catalog",
  context: { skill_id: "gf-pgs-crosslist-sync-protocol" },
  dry_run: false,
});
// result.ok, result.steps, result.artifacts
```

## Pay path

1. Free: this sample + outline.json  
2. `GET https://lvlltd.com/api/pay?skill=gf-pgs-crosslist-sync-protocol` → HTTP 402  
3. Transfer `maxAmountRequired` USDC to `payTo` on Base  
4. `POST /api/pay` with `X-PAYMENT: {"txHash":"0x…","skill":"gf-pgs-crosslist-sync-protocol"}`  
5. Write `sealed_pack.files` to disk or use install-unlocked-pack.mjs  
6. Re-redeem anytime with the same verified txHash  

## Honesty

- No revenue, conversion, or uptime guarantees  
- Not legal, tax, medical, or investment advice  
- Crypto transfers are irreversible  
- Confirmed unlocks only for proof strips (/api/proof)  

*Public `/sealed/gf-pgs-crosslist-sync-protocol/` is teaser-only. Full `src/` is paywalled under locked sealed delivery.*