The URL has a typo — double-check the hostname
The server is on a private/corporate network or VPN that isn't reachable from the public internet — this tool can only debug publicly accessible servers
The domain's DNS is not configured yet

`\n ));\n return { steps };\n }\n // DNS is fine — connection-level failure\n const errorMsg = initError instanceof Error ? initError.message : String(initError);\n steps.push(createErrorStep(\n \"Error: Connection Failed\",\n `DNS resolved ${hostname} to ${dns.addresses?.join(\", \") ?? \"unknown\"}, ` +\n `but the connection failed: ${errorMsg}. ` +\n `Is the MCP server running and accepting connections on this URL?`\n ));\n return { steps };\n }\n\n // Step 2: Run SDK auth() for discovery, registration, and auth URL generation\n const result = await auth(provider, {\n serverUrl,\n resourceMetadataUrl,\n fetchFn: debugFetch,\n });\n\n // Add result step\n steps.push({\n id: crypto.randomUUID(),\n label: \"Auth Flow Result\",\n request: { method: \"INFO\", url: \"\", headers: {} },\n response: {\n status: 0,\n statusText: \"Info\",\n headers: {},\n body: {\n message: result === \"REDIRECT\"\n ? \"Successfully generated authorization URL\"\n : `Auth result: ${result}`,\n },\n },\n });\n\n return {\n steps,\n authorizationUrl: provider.authUrl?.toString(),\n codeVerifier: provider._codeVerifier ?? undefined,\n };\n } catch (error) {\n steps.push({\n id: crypto.randomUUID(),\n label: \"Flow Error\",\n request: { method: \"ERROR\", url: \"\", headers: {} },\n response: {\n status: 0,\n statusText: \"Error\",\n headers: {},\n body: {\n message: error instanceof Error ? error.message : String(error),\n },\n },\n });\n return { steps };\n }\n}\n","deleted","label",[175,157],"lib","permalink","https://www.val.town/x/pcarleton/mcp-oauth-debugger/code/lib/oauth-flow.ts","extension","actionData","errors"]