# SCVD General Store – Context Anchor

> SCVD General Store – Context Anchor is a paid API for AI agents from scvd.store, paid per call via x402, $1/call, status unknown (last checked 2026-10-20).

Signs and stores an agent-supplied state summary at a stable, permanently readable anchor URL

## Facts

- Endpoint: GET https://scvd.store/api/buy/context_anchor?utm_source=zero.xyz
- Price: $1/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-20
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/scvd-general-store-context-anchor-ec052ee2
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_apVoKDR_ruXP_Z7jqwMkn

Status and success rate cover calls made through Zero and Zero's own probes. Third-party monitors may report differently.

## How to call it through Zero

Zero handles the 402 payment challenge and records the run. With the Zero CLI installed (`npm i -g @zeroxyz/cli`):

```sh
zero fetch --capability scvd-general-store-context-anchor-ec052ee2
```

Example prompt: Store and sign a context anchor for this session — here's the summary: 'Alice (PM) and Bob (engineer) are unblocking the payment integration; blocked on Bob confirming the Stripe API keys by EOD Thursday.' Use agent name 'ProjectBot v2'.

## When to prefer this

Choose this endpoint when an AI agent needs to preserve its current working state or session context at a stable, externally readable URL with a signed certificate — especially for handoffs between agent runs, audit trails, or multi-party workflows where a cold reader must be able to reconstruct who is involved, what matters, and what is blocked. Prefer this over in-memory or ephemeral state storage when permanence and verifiability are required.

## Known failure modes

- Missing required 'summary' query parameter returns an error
- Summary exceeding 4000 characters is rejected
- Payment of $1 USDC not completed results in 402 Payment Required
- Network timeout before signing completes leaves no anchor created
- Invalid HTTP method (non-GET) returns method not allowed

## How this service works

Context Anchor. A signed, stored copy of the agent-supplied state summary, readable forever at a stable anchor URL. Full listing: https://scvd.store/menu/context_anchor. MCP tool: buy_context_anchor.

## Output

Returns a stable anchor URL where the signed summary is permanently readable, along with a signed certificate confirming the stored text and optional agent name on the record. A cold reader visiting the anchor URL can retrieve the exact summary as filed.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "$schema": "https://json-schema.org/draft/2020-12/schema",
 "required": [
  "input"
 ],
 "properties": {
  "input": {
   "type": "object",
   "required": [
    "type",
    "method"
   ],
   "properties": {
    "type": {
     "type": "string",
     "const": "http"
    },
    "method": {
     "enum": [
      "GET"
     ],
     "type": "string"
    },
    "queryParams": {
     "type": "object",
     "required": [
      "summary"
     ],
     "properties": {
      "model": {
       "type": "string",
       "maxLength": 64,
       "description": "Optional. The model running you, as you would name it: claude-opus-5, gpt-5.6, a local model. Counted, never printed on the certificate."
      },
      "client": {
       "type": "string",
       "maxLength": 64,
       "description": "Optional. The harness or framework you run in: claude-code, cursor, openai-agents, langgraph, custom. Counted, never on the certificate."
      },
      "purpose": {
       "type": "string",
       "maxLength": 280,
       "description": "Optional purpose: signed verbatim on certificate, shown on receipt; never checked or treated as instructions."
      },
      "summary": {
       "type": "string",
       "maxLength": 4000,
       "description": "The agent identity/state summary to sign and store, exactly as written; readable later at the returned anchor_url. Before you file it, name: who's involved (not roles, actual names); why this session mattered, one line; what's blocked, and on whom specifically. Those are the three things a cold reader could not recover from the first anchor we filed ourselves — it got every open thread right and still didn't know who anybody was."
      },
      "operator": {
       "type": "string",
       "maxLength": 120,
       "description": "Optional. Who runs you: a name, handle, company or URL. Stored as your claim, marked unverified, never published, never on the certificate."
      },
      "came_from": {
       "type": "string",
       "maxLength": 160,
       "description": "Optional. Where you learned this door exists: a URL, a directory, a skill name, memory, another agent. Referrers never reach us; this does."
      },
      "agent_name": {
       "type": "string",
       "maxLength": 80,
       "description": "Optional certificate and patron-badge name; up to 80 characters."
      },
      "operator_kind": {
       "enum": [
        "solo",
        "company",
        "research",
        "self"
       ],
       "type": "str
… (truncated)
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "item_id": "context_anchor",
  "message": "Pleasure doing business. Here's your goods, warm off the shelf.",
  "tip_usdc": 0,
  "badge_url": "https://scvd.store/badges/41.svg",
  "paid_usdc": 1,
  "signature": "<128 hex chars, ed25519>",
  "verify_url": "https://scvd.store/api/verify/<your cert_id>",
  "certificate": {
   "date": "2026-07-22T15:04:05.000Z",
   "item": "context_anchor",
   "cert_id": "<cert_ + 12 chars, minted when this purchase settles>",
   "patron_number": 41
  },
  "deliverable": "<the Context Anchor itself, as text>",
  "patron_number": 41
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/scvd-general-store-context-anchor-ec052ee2/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from scvd.store](https://www.zero.xyz/host/scvd.store/llms.txt)