What is Nall.Hangfire.Mcp?

Nall.Hangfire.Mcp is a remote MCP server that exposes Hangfire background jobs as MCP tools, in-process with the ASP.NET host that runs Hangfire. Any MCP-capable client (VS Code, Claude Desktop, custom agents) can list and invoke your jobs over a Streamable HTTP endpoint at /mcp.

Design

• In-process. Runs inside the ASP.NET host that runs Hangfire. No out-of-process assembly loading.
• Remote. Streamable HTTP endpoint at /mcp. Any MCP client (VS Code, Claude Desktop, custom agents) can connect.
• Zero ceremony. No attributes, no shim interfaces — discovery reads what you already register with Hangfire.
• Schema from MethodInfo. JSON Schema generated per method. Required vs. optional respects both C# defaults and nullable annotations (int?, string?).

Pipeline

1. Discovery — at startup, JobCatalog reads recurring job registrations from Hangfire storage and/or a compile-time manifest emitted by the source generator.
2. Schema — each job method becomes an MCP tool. Parameter types, C# defaults, and nullability annotations are translated to a JSON Schema (required vs optional).
3. Invocation — when an AI calls a tool, the library binds the JSON arguments, builds a Hangfire.Common.Job, and enqueues it via IBackgroundJobClient. The job runs normally through the Hangfire server.

Tool call sequence

Next steps

• Getting Started — install and wire up in three lines.
• Discovery Sources — choose between recurring storage and the compile-time manifest.
• Authentication — layer OAuth 2.1 / OIDC on top of MapHangfireMcp.