geo_mcp_server: Skill for Claude Code

MCP Tool Result Detection Patterns

When detecting specific payloads in MCP tool results (e.g., transaction signing requests, payment receipts), three non-obvious preprocessing steps are required. These patterns were discovered through debugging and are implemented identically in:

• rickydata_SDK/packages/core/src/geo-wallet/detect.ts
• mcp-agent-gateway/src/chat/chat-service.ts

1. Slug-Based Tool Name Prefix Stripping

The MCP gateway returns tool names with a server slug prefix (e.g., rickycambrian-geo-mcp-server__publish_edit). To match against a known tool list, strip the prefix:

const bareToolName = toolName.includes('__')
  ? toolName.slice(toolName.lastIndexOf('__') + 2)
  : toolName;

Why lastIndexOf: The slug can itself contain special characters; using lastIndexOf('__') ensures we split at the actual delimiter, not a coincidental match in the slug.

This mirrors the gateway's own slug generation algorithm (from the MCP Gateway Slug-Based Tool Prefix Fix, commit b7aabe0e):

name.toLowerCase().replace(/[^a-z0-9]+/g, '-').replace(/^-|-$/g, '').slice(0, 50)

2. x402 Payment Receipt Stripping

When x402 payments are enabled, the gateway appends a JSON payment receipt on a new line after the tool result. This must be stripped before JSON parsing:

const cleanResult = toolResult.split('\n{"_payment"')[0].trim();

This handles the format: {"actual":"result"}\n{"_payment":{"receipt":"...","amount":"0.001"}}

3. Dual JSON Format Parsing

MCP tool results can arrive in two formats:

Format A — Direct JSON: The tool result string is the JSON object directly.

{"status": "pending_signature", "id": "abc123", "to": "0x...", "data": "0x..."}

Format B — MCP Content Array: The result is wrapped in the MCP content structure.

{"content": [{"type": "text", "text": "{\"status\":\"pending_signature\",\"id\":\"abc123\",...}"}]}

The detection function must try both:

// Try direct parse first
try {
  const parsed = JSON.parse(cleanResult);
  const result = extractPayload(parsed);
  if (result) return result;
} catch { /* not direct JSON */ }

// Try MCP content array format
try {
  const parsed = JSON.parse(cleanResult);
  if (Array.isArray(parsed.content)) {
    for (const item of parsed.content) {
      if (item.type === 'text' && typeof item.text === 'string') {
        try {
          // Strip x402 receipt from inner text too
          const inner = JSON.parse(item.text.split('\n{"_payment"')[0].trim());
          const result = extractPayload(inner);
          if (result) return result;
        } catch { /* inner text wasn't JSON */ }
      }
    }
  }
} catch { /* not parseable at all */ }