Ainumbers MCP Apps

What PostOakLabs/ainumbers-mcp-apps does

PostOakLabs/ainumbers-mcp-apps exposes the AINumbers.co fintech catalog through MCP. Its surface combines discovery utilities, deterministic ChainGraph computations, workflow orchestration, artifact verification, and 15 interactive MCP Apps widgets. The widgets cover areas such as BaaS provider evaluation, AP2 mandates, agentic payment policies, customer risk rating, x402, Visa TAP, A2A agent cards, MCP OAuth, tool poisoning, and server-readiness checks.

The server is read-only. It does not require an account, API key, or authentication, and its tools are designed for zero PII and zero payload logging. The live service runs at https://mcp.ainumbers.co/mcp.

How it works

Discovery tools search the AINumbers catalog and ChainGraph registry. find_tool locates individual computation nodes, while find_chain returns ordered recipes for multi-step workflows. list_ainumbers_tools and build_workflow_links can return browser deep-links, including prefilled inputs encoded in URL fragments.

For verifiable execution, build_chaingraph describes DAG order and parent-hash wiring. emit_chaingraph_artifact can validate a browser-produced artifact, create a prefilled browser handoff, or run a registered non-GPU kernel server-side. run_chain executes named chains and returns a composite artifact; verify_execution_hash independently recomputes its SHA-256 integrity hash. build_session_receipt combines execution hashes into a Merkle-rooted session receipt.

Hash-bound inputs must follow I-JSON rules. Integers above 2^53 must be represented as JSON strings, and NaN or Infinity values are rejected.

Setup and configuration

Use the hosted endpoint with an MCP client that supports Streamable HTTP. Claude can add it as a custom connector using:

https://mcp.ainumbers.co/mcp

The MCP Inspector can connect through its Streamable HTTP option. Cursor and other Open Plugins directories can discover the endpoint from the repository’s root .mcp.json.

To self-host, fork the repository and deploy it to Cloudflare Workers. Rename the Worker and remove or change the example route before deployment. The optional queue and workflow bindings support an internal analytics loop but are not needed for the MCP handshake or tool calls. Local development uses npm install, node generate.mjs, and npm start; the local Express variant listens on port 3300.

Tools and capabilities

• Search tools, chains, and catalog entries with find_tool, find_chain, list_ainumbers_tools, and describe_tool.
• Construct browser workflows or ChainGraph DAGs with build_workflow_links and build_chaingraph.
• Execute named chains individually or in batches with run_chain and run_chain_batch.
• Verify artifacts, input attestations, and session integrity with verify_execution_hash, validate_input_attestations, and build_session_receipt.
• Call catalog tools outside the host’s visible tool list through call_tool.
• Use widgets for payment-policy simulation, BaaS comparison, AML/KYC analysis, protocol inspection, and MCP validation.

Limitations and notes

Browser-only or GPU-backed tools require delegation through an AINumbers browser link. Server-side computation is available for registered kernels and does not replace browser execution for GPU tools. Workflow batches are capped at eight rows and eleven total server-kernel steps on the deployed free-plan endpoint.

The repository stores generated catalog and kernel artifacts. Changes in the related AINumbers site repository require regeneration before deployment so the Worker does not serve stale data. The code is MIT licensed; tool content is CC BY 4.0 from Post Oak Labs.