Add SCVD General Store (two skills, one MCP server)

[cv-scvd]

Adds three augments from seancrecord/scvd-general-store-repo (MIT), the repository behind scvd.store, an evidence observatory for agentic commerce: independent verification of x402 endpoints, payments and receipts.

Entries

file	media type	definition
scvd-general-store.json	application/ai-skill	skills/scvd-general-store/SKILL.md — how an agent reads, verifies and buys at the store
x402-before-you-pay.json	application/ai-skill	examples/claude-code/SKILL.md — read a 402's terms and run the free preflight before paying any x402 endpoint
scvd-general-store-mcp.json	application/mcp-server+json	store.scvd/general-store on the official MCP registry, streamable HTTP at https://scvd.store/mcp

What a Copilot user gets from these

• Before paying an x402 endpoint: POST https://scvd.store/api/before-you-pay/v1 with the URL says whether a stock client would sign, which offer it would pick, and what the door's shape looks like. Free, no key.
• Conformance checks for any issuer's signed x402 offers and receipts, ours or a competitor's: POST https://scvd.store/api/conformance/v1. Free.
• A weekly, Bitcoin-anchored corpus of observed endpoint readiness (CC BY 4.0), per host at /corpus/host/{host}.json.
• A live practice counter for x402 clients with real settlement from $0.001, and paid signed audits, watches and settlement attestations from $0.004.

What they do not do

The skills instruct an agent to call public HTTPS endpoints and to read their answers; they declare no environment variables, no binaries and no install steps. Nothing asks for credentials, keys or wallet secrets, and nothing pays without a signed payment the agent's operator chose to make. The MCP server's tools/list, initialize and resource reads are free and unauthenticated; the buy_* tools answer with HTTP 402 x402 terms and settle only in band.

Validation

• Every URL is public; each metadata.repoPath exists on main in the named sourceSet.
• python3 scripts/generate_ai_catalog.py --check passes locally on all three files.
• The MCP entry's version and description repeat the registry's latest published version verbatim; a test in the source repository (scripts/agentfinder-check.test.mjs) refuses drift between these files and the manifests they describe.

Notes for the reviewer: the MCP entry uses the urn:ai:registry.modelcontextprotocol.io:<namespace>:<name> identifier shape your generator emits for feed rows, so that if GitHub's MCP feed later carries this server the generator dedupes to one row. Happy to switch it to the urn:ai:github.com:... shape if you prefer contributor entries uniform.