# io.github.MitchSingh/402shield

> x402 payment security and pre-execution transaction risk screening for autonomous AI agents.

- name: io.github.MitchSingh/402shield
- version: 0.1.0
- connection class: R0 (autonomous)
- trust: 94/100
- quality: 73/100 (needs work)
- owner: not claimed
- descriptor: https://api.protogrid.dev/v1/servers/io.github.MitchSingh%2F402shield
- tools: https://api.protogrid.dev/v1/servers/io.github.MitchSingh%2F402shield/tools

**An agent can connect right now, no human step.** Remote endpoint, no authentication, reachable on the last probe.

## Connection (mcpServers)

```json
{
  "mcpServers": {
    "402shield": {
      "type": "http",
      "url": "https://four02shield.onrender.com/mcp"
    }
  }
}
```


## Trust

- hygiene: 100
- liveness: 100
- freshness: 100
- provenance: 80
- drivers: +repository +namespace-matches-repo +reachable +uptime-100% +updated-13d-ago
- Derived from observable signals (official registry feed and our own credential-free probes); no code audit performed.

## Quality 73/100 (needs work)

### protocol: 88 (weight 25)

- pass `protocol.modern`: supports 2026-07-28 (server/discover)
- pass `protocol.stateless`: answers without a session
- pass `protocol.transport`: streamable HTTP
- warn `protocol.list_ttl`: tools/list declares ttlMs 0, so clients re-fetch it on every use

### authorization: n/a (weight 15)

- n/a `auth.prm`, `auth.as_metadata`, `auth.cimd`: no remote uses OAuth
- n/a `auth.secret_in_url`: no templated URL

### tool hygiene: 71 (weight 30)

- pass `tools.descriptions`: every tool has a description
- pass `tools.description_length`: descriptions are concise
- pass `tools.schemas`: every tool has an object input schema
- fail `tools.annotations`: no tool declares readOnlyHint or destructiveHint, so clients cannot tell safe calls from risky ones
- fail `tools.directory_hints`: no tool declares all four of readOnlyHint, destructiveHint, idempotentHint and openWorldHint; missing: preflight_payment (readOnlyHint, destructiveHint, idempotentHint, openWorldHint)
- pass `tools.token_cost`: about 315 tokens to load every tool
- pass `tools.api_dump`: tools are not a one-to-one API dump

### stability: 50 (weight 15)

- pass `stability.changes`: 2 tool changes in 30 days
- fail `stability.rug_pull`: 1 tools kept their name but changed most of their description in 30 days; review before trusting them

### dependencies: n/a (weight 15)

- n/a `deps.known_vulns`, `deps.mcp_sdk_version`, `deps.resolvable`: no npm or PyPI package

- tools: 1, about 315 tokens to load them all
- tool set hash: f382653de2e960d3b3109b9726c51106
- tools last changed: 2026-10-08T12:16:00.326Z
- badge: [![protogrid quality](https://protogrid.dev/badge/io.github.MitchSingh/402shield.svg)](https://protogrid.dev/servers/io.github.MitchSingh/402shield)
- Checks run on what our credential-free, read-only probes observe; tools are never called and no code audit is performed.

### Tool changes

- 2026-10-08 `preflight_payment` changed (description, outputSchema) **meaning changed**
  - before: Prepare a paid 402Shield pre-execution safety check. The returned endpoint costs $0.005 USDC via x402 and returns ALLOW, REVIEW, or BLOCK. This MCP adapter does not bypass payment.
  - after: Prepare the exact paid 402Shield request that must be completed before an autonomous payment executes. Submit the returned POST request with an x402-capable client. The paid response is ALLOW, REVIEW, or BLOCK. Execute the intended payment only after ALLOW; REVIEW and BLOCK should stop execution by default. Price: $0.005 USDC.
- 2026-10-07 `preflight_payment` changed (description)
  - before: Prepare a paid 402Shield pre-execution safety check. The returned endpoint costs $0.05 USDC via x402 and returns ALLOW, REVIEW, or BLOCK. This MCP adapter does not bypass payment.
  - after: Prepare a paid 402Shield pre-execution safety check. The returned endpoint costs $0.005 USDC via x402 and returns ALLOW, REVIEW, or BLOCK. This MCP adapter does not bypass payment.

Full history: https://api.protogrid.dev/v1/servers/io.github.MitchSingh%2F402shield/changes

## Remotes

- https://four02shield.onrender.com/mcp (streamable-http, auth none, reachable true, uptime30d 1)

## Packages

_none_

## Tools (1)

- `preflight_payment`: Prepare the exact paid 402Shield request that must be completed before an autonomous payment executes. Submit the returned POST request with an x402-capable client. The paid response is ALLOW, REVIEW, or BLOCK. Execute the intended payment only after ALLOW; REVIEW and BLOCK should stop execution by default. Price: $0.005 USDC.