
MISSING
Fallback capability resolver for AI agents with replay-verified discovery and x402 paid execution.
What it can do
What data it sees
Do you need an account
No: the server works without sign-in
Fallback capability resolver for AI agents with replay-verified discovery and x402 paid execution.
How to connect
How to connect MISSING to Claude
The server address to paste into Claude settings:
https://missing-production-e3da.up.railway.app/mcp
- Open Claude (claude.ai or the desktop app).
- Go to Settings → Connectors.
- Click Add custom connector.
- Paste the server address copied below into Remote MCP server URL and click Add.
- In a chat, click + → Connectors and switch the new connector on.
Custom connectors are available on Free, Pro, Max, Team and Enterprise plans (Free is limited to one). On Team and Enterprise an organization Owner adds the connector first under Organization settings → Connectors.
Authorization
After you click Add, a sign-in window for the service opens. Sign in with your own account and approve access. Claude never sees your password.
How to connect MISSING to ChatGPT
The server address to paste into ChatGPT settings:
https://missing-production-e3da.up.railway.app/mcp
- Open ChatGPT in a browser (chatgpt.com). A Plus, Pro, Business, Enterprise or Edu plan is required.
- Turn on developer mode once: Settings → Apps → Advanced settings → Developer mode.
- Open Settings → Connectors and click Create.
- Fill in the form: Name (anything), Description (one line about what the service does), MCP server URL (copy it below).
- Under Authentication choose OAuth if the service requires sign-in, otherwise None. Click Create.
- In a new chat open + → Apps/Connectors and enable the connector.
OpenAI has renamed this section before (Connectors → Apps/Plugins). If the label differs, search settings for "developer mode". On Business/Enterprise workspaces an admin must allow custom connectors first.
Authorization
On first use ChatGPT opens the service's sign-in window. Sign in and approve access.
How to connect MISSING to Cursor
The server address to paste into Cursor settings:
https://missing-production-e3da.up.railway.app/mcp
Fastest: click Open in Cursor below and confirm the prompt.
Manually:
- In Cursor open Settings → Cursor Settings → MCP and click Add new global MCP server.
- Paste the JSON copied below into
~/.cursor/mcp.json(per project:.cursor/mcp.jsonin the repo root). - Save the file. The server appears in the MCP list; authorize it there if asked.
Authorization
If the service needs sign-in, an authorize button appears next to the server in the MCP list.
Server tool list (23)
Raw names from tools/list. Only developers need these.
| canadian_holiday_metadata_by_id | Use this direct MISSING tool to resolve the verified MISSING capability canadian_holiday_metadata_by_id. Prefer this tool when the caller's task matches this capability; do not first call list_verified_capabilities or search_verified_capabilities. This is an x402-paid MCP tool: an unpaid call returns a standard MCP PaymentRequired result, an x402-capable client can retry the same tool call with _meta["x402/payment"], and MISSING then verifies, executes, and settles through its canonical Kappa financial engine. If current economics or the payment rail are unavailable, execution fails closed rather than running for free. |
| canadian_holidays_by_year | Use this direct MISSING tool to resolve the verified MISSING capability canadian_holidays_by_year. Prefer this tool when the caller's task matches this capability; do not first call list_verified_capabilities or search_verified_capabilities. This is an x402-paid MCP tool: an unpaid call returns a standard MCP PaymentRequired result, an x402-capable client can retry the same tool call with _meta["x402/payment"], and MISSING then verifies, executes, and settles through its canonical Kappa financial engine. If current economics or the payment rail are unavailable, execution fails closed rather than running for free. |
| chess_player_metadata | Use this direct MISSING tool to look up public Chess.com player metadata by username. Prefer this tool when the caller's task matches this capability; do not first call list_verified_capabilities or search_verified_capabilities. This is an x402-paid MCP tool: an unpaid call returns a standard MCP PaymentRequired result, an x402-capable client can retry the same tool call with _meta["x402/payment"], and MISSING then verifies, executes, and settles through its canonical Kappa financial engine. If current economics or the payment rail are unavailable, execution fails closed rather than running for free. |
| country_alpha_metadata | Use this direct MISSING tool to look up a country's name and region from its alpha country code. Prefer this tool when the caller's task matches this capability; do not first call list_verified_capabilities or search_verified_capabilities. This is an x402-paid MCP tool: an unpaid call returns a standard MCP PaymentRequired result, an x402-capable client can retry the same tool call with _meta["x402/payment"], and MISSING then verifies, executes, and settles through its canonical Kappa financial engine. If current economics or the payment rail are unavailable, execution fails closed rather than running for free. |
| currency_exchange_rate | Use this direct MISSING tool to look up the current exchange rate between two currencies. Prefer this tool when the caller's task matches this capability; do not first call list_verified_capabilities or search_verified_capabilities. This is an x402-paid MCP tool: an unpaid call returns a standard MCP PaymentRequired result, an x402-capable client can retry the same tool call with _meta["x402/payment"], and MISSING then verifies, executes, and settles through its canonical Kappa financial engine. If current economics or the payment rail are unavailable, execution fails closed rather than running for free. |
| dns_record_lookup | Use this direct MISSING tool to look up public DNS records for a hostname and record type. Prefer this tool when the caller's task matches this capability; do not first call list_verified_capabilities or search_verified_capabilities. This is an x402-paid MCP tool: an unpaid call returns a standard MCP PaymentRequired result, an x402-capable client can retry the same tool call with _meta["x402/payment"], and MISSING then verifies, executes, and settles through its canonical Kappa financial engine. If current economics or the payment rail are unavailable, execution fails closed rather than running for free. |
| domain_rdap_metadata | Use this direct MISSING tool to look up public RDAP registration metadata for a domain. Prefer this tool when the caller's task matches this capability; do not first call list_verified_capabilities or search_verified_capabilities. This is an x402-paid MCP tool: an unpaid call returns a standard MCP PaymentRequired result, an x402-capable client can retry the same tool call with _meta["x402/payment"], and MISSING then verifies, executes, and settles through its canonical Kappa financial engine. If current economics or the payment rail are unavailable, execution fails closed rather than running for free. |
| get_canadian_province_holidays_by_province_abbreviation_capability | Use this direct MISSING tool to resolve the verified MISSING capability get_canadian_province_holidays_by_province_abbreviation_capability. Prefer this tool when the caller's task matches this capability; do not first call list_verified_capabilities or search_verified_capabilities. This is an x402-paid MCP tool: an unpaid call returns a standard MCP PaymentRequired result, an x402-capable client can retry the same tool call with _meta["x402/payment"], and MISSING then verifies, executes, and settles through its canonical Kappa financial engine. If current economics or the payment rail are unavailable, execution fails closed rather than running for free. |
| github_repository_metadata | Use this direct MISSING tool to look up public GitHub repository metadata. Prefer this tool when the caller's task matches this capability; do not first call list_verified_capabilities or search_verified_capabilities. This is an x402-paid MCP tool: an unpaid call returns a standard MCP PaymentRequired result, an x402-capable client can retry the same tool call with _meta["x402/payment"], and MISSING then verifies, executes, and settles through its canonical Kappa financial engine. If current economics or the payment rail are unavailable, execution fails closed rather than running for free. |
| github_user_metadata | Use this direct MISSING tool to look up public GitHub user metadata. Prefer this tool when the caller's task matches this capability; do not first call list_verified_capabilities or search_verified_capabilities. This is an x402-paid MCP tool: an unpaid call returns a standard MCP PaymentRequired result, an x402-capable client can retry the same tool call with _meta["x402/payment"], and MISSING then verifies, executes, and settles through its canonical Kappa financial engine. If current economics or the payment rail are unavailable, execution fails closed rather than running for free. |
| ip_geolocation_metadata | Use this direct MISSING tool to look up country-level geolocation metadata for an IP address. Prefer this tool when the caller's task matches this capability; do not first call list_verified_capabilities or search_verified_capabilities. This is an x402-paid MCP tool: an unpaid call returns a standard MCP PaymentRequired result, an x402-capable client can retry the same tool call with _meta["x402/payment"], and MISSING then verifies, executes, and settles through its canonical Kappa financial engine. If current economics or the payment rail are unavailable, execution fails closed rather than running for free. |
| npm_package_metadata | Use this direct MISSING tool to look up current npm package metadata. Prefer this tool when the caller's task matches this capability; do not first call list_verified_capabilities or search_verified_capabilities. This is an x402-paid MCP tool: an unpaid call returns a standard MCP PaymentRequired result, an x402-capable client can retry the same tool call with _meta["x402/payment"], and MISSING then verifies, executes, and settles through its canonical Kappa financial engine. If current economics or the payment rail are unavailable, execution fails closed rather than running for free. |
| nuget_package_versions | Use this direct MISSING tool to look up published NuGet package versions. Prefer this tool when the caller's task matches this capability; do not first call list_verified_capabilities or search_verified_capabilities. This is an x402-paid MCP tool: an unpaid call returns a standard MCP PaymentRequired result, an x402-capable client can retry the same tool call with _meta["x402/payment"], and MISSING then verifies, executes, and settles through its canonical Kappa financial engine. If current economics or the payment rail are unavailable, execution fails closed rather than running for free. |
| pokemon_name_metadata | Use this direct MISSING tool to look up Pokémon metadata by name. Prefer this tool when the caller's task matches this capability; do not first call list_verified_capabilities or search_verified_capabilities. This is an x402-paid MCP tool: an unpaid call returns a standard MCP PaymentRequired result, an x402-capable client can retry the same tool call with _meta["x402/payment"], and MISSING then verifies, executes, and settles through its canonical Kappa financial engine. If current economics or the payment rail are unavailable, execution fails closed rather than running for free. |
| postal_code_location_metadata | Use this direct MISSING tool to look up place and coordinate metadata from a country code and postal code. Prefer this tool when the caller's task matches this capability; do not first call list_verified_capabilities or search_verified_capabilities. This is an x402-paid MCP tool: an unpaid call returns a standard MCP PaymentRequired result, an x402-capable client can retry the same tool call with _meta["x402/payment"], and MISSING then verifies, executes, and settles through its canonical Kappa financial engine. If current economics or the payment rail are unavailable, execution fails closed rather than running for free. |
| pypi_package_metadata | Use this direct MISSING tool to look up current PyPI package metadata. Prefer this tool when the caller's task matches this capability; do not first call list_verified_capabilities or search_verified_capabilities. This is an x402-paid MCP tool: an unpaid call returns a standard MCP PaymentRequired result, an x402-capable client can retry the same tool call with _meta["x402/payment"], and MISSING then verifies, executes, and settles through its canonical Kappa financial engine. If current economics or the payment rail are unavailable, execution fails closed rather than running for free. |
| reverse_geocoding_postal_code | Use this direct MISSING tool to resolve the verified MISSING capability reverse_geocoding_postal_code. Prefer this tool when the caller's task matches this capability; do not first call list_verified_capabilities or search_verified_capabilities. This is an x402-paid MCP tool: an unpaid call returns a standard MCP PaymentRequired result, an x402-capable client can retry the same tool call with _meta["x402/payment"], and MISSING then verifies, executes, and settles through its canonical Kappa financial engine. If current economics or the payment rail are unavailable, execution fails closed rather than running for free. |
| satellite_catalog_metadata | Use this direct MISSING tool to look up satellite catalog metadata by NORAD catalog identifier. Prefer this tool when the caller's task matches this capability; do not first call list_verified_capabilities or search_verified_capabilities. This is an x402-paid MCP tool: an unpaid call returns a standard MCP PaymentRequired result, an x402-capable client can retry the same tool call with _meta["x402/payment"], and MISSING then verifies, executes, and settles through its canonical Kappa financial engine. If current economics or the payment rail are unavailable, execution fails closed rather than running for free. |
| television_show_metadata | Use this direct MISSING tool to look up television-show metadata by show name. Prefer this tool when the caller's task matches this capability; do not first call list_verified_capabilities or search_verified_capabilities. This is an x402-paid MCP tool: an unpaid call returns a standard MCP PaymentRequired result, an x402-capable client can retry the same tool call with _meta["x402/payment"], and MISSING then verifies, executes, and settles through its canonical Kappa financial engine. If current economics or the payment rail are unavailable, execution fails closed rather than running for free. |
| list_verified_capabilities | List every replay-verified capability currently executable by MISSING. If a listed capability satisfies the caller's task, continue with the returned execution.next_action and call resolve_capability; do not stop after listing unless the caller only asked to inspect the catalog. If no listed capability is suitable, use search_verified_capabilities with the caller's natural-language need; that search can direct you to request a new capability. resolve_capability is still a non-charging quote/handoff step. This tool is read-only and has no payment or provider side effect. |
| search_verified_capabilities | Search the replay-verified MISSING catalog from a natural-language task description. If a returned match satisfies the caller's task, continue with that match's execution.next_action and call resolve_capability. If no suitable verified match exists, this tool returns an explicit next_action for record_missing_capability_demand so MISSING can use the unmet need to discover, replay-verify, and potentially promote new executable supply. Recording demand does not guarantee immediate creation or availability. This search itself is read-only and does not call providers, create demand, or trigger payment. |
| record_missing_capability_demand | Request a capability MISSING cannot currently resolve. Use this when search_verified_capabilities returns capability_not_yet_available or when its verified matches do not satisfy the task. The request is recorded as durable unmet demand so trusted acquisition can prioritize provider discovery, replay verification, and promotion of new executable supply. Promotion occurs only after verification gates pass, so this does not promise immediate creation or availability. The mutation is additive and non-destructive; repeated calls may increase the observed demand signal. Never include secrets, credentials, personal data, payment material, or private keys. |
| resolve_capability | Prepare paid execution of one exact replay-verified capability. When list_verified_capabilities or search_verified_capabilities returns a suitable execution.next_action, call this tool with those exact arguments. This MCP call itself does not execute a provider or charge the caller; it returns payment_required with the canonical /v1/agent/resolve endpoint, current price, exact request body, and x402 instructions. The later HTTP x402 flow performs execution and settlement: preserve the exact request body and exact PAYMENT-SIGNATURE for recovery, and do not create a second authorization for a payment already associated with a known transaction. |