> ## Documentation Index
> Fetch the complete documentation index at: https://docs.thespawn.io/llms.txt
> Use this file to discover all available pages before exploring further.

# MCP JSON-RPC checks

> Verify initialize, tools/list, and one safe tools/call before you treat an MCP endpoint as working.

MCP metadata is not execution proof. A working endpoint should answer tool discovery. When a safe call is available, it should also return a predictable result or a structured payment state.

## Tool discovery

```bash theme={null}
curl -sS https://socialintel.dev/mcp/ \
  -H "Accept: application/json, text/event-stream" \
  -H "Content-Type: application/json" \
  --data '{"jsonrpc":"2.0","id":"tools-list","method":"tools/list","params":{}}'
```

Expected signal:

```text theme={null}
"name":"search_leads"
```

## Hosted runtime call

```bash theme={null}
curl -sS https://thespawn.io/mcp \
  -H "Accept: application/json, text/event-stream" \
  -H "Content-Type: application/json" \
  --data '{"jsonrpc":"2.0","id":"search","method":"tools/call","params":{"name":"spawnr_search","arguments":{"query":"instagram influencer finder","limit":2}}}'
```

Expected signal:

```text theme={null}
"Social Intel API"
"base"
```

For Social Intel API itself, the direct MCP `tools/list` check is the stable first-run probe. Its demo bridge can rate-limit `tools/call`; the direct demo request in [Quickstart](/quickstart) is the current no-payment output proof.

## Initialize

Some HTTP MCP servers require `initialize` before `tools/list`.

```bash theme={null}
curl -sS https://example.com/mcp \
  -H "Accept: application/json, text/event-stream" \
  -H "Content-Type: application/json" \
  --data '{"jsonrpc":"2.0","id":"init","method":"initialize","params":{"protocolVersion":"2024-11-05","clientInfo":{"name":"spawnr-docs","version":"1"},"capabilities":{}}}'
```

If the server returns `Mcp-Session-Id`, send that header on later requests to the same endpoint.

## Quality interpretation

| State           | Meaning                                                                        |
| --------------- | ------------------------------------------------------------------------------ |
| Declared MCP    | Metadata says there is an MCP endpoint.                                        |
| Listed tools    | `tools/list` returned at least one tool.                                       |
| Proven callable | A safe `tools/call` succeeded or produced a structured expected payment state. |

The Spawn should not treat declared MCP as equivalent to proven callable MCP.

## Next

* [spawnr MCP runtime](/mcp/runtime)
* [Let agents use your service](/paths/let-agents-use-your-service)
* [Improve agent quality](/paths/improve-agent-quality)