Database routing via URL path (HTTP mode)

[MacondoExpress]

Breaking change — must NOT be merged into main. Target branch: v2.

Context

The Neo4j MCP server currently accepts only a single database per deployment, configured at startup via the NEO4J_DATABASE environment variable or CLI argument. As part of the multi-tenant proposal, the database name must become a per-request concern in HTTP mode, expressed directly in the URL path.

The new path format is:

/db/{databaseName}/mcp/

When the {databaseName} segment is absent the server should fail.

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Goals

1 — Expose the new URL path handler

Register the /db/{databaseName}/mcp/ route in the HTTP server replacing the existing /mcp route.

2 — Extract database name from URL path and inject into context.Context

Parse {databaseName} from the matched route and place it on the request context so the Neo4j driver can consume it downstream, mirroring the existing pattern used for auth headers.

3 — Raise an error when NEO4J_DATABASE or --neo4j-database is set in HTTP mode

The NEO4J_DATABASE environment variable and its CLI argument equivalent are meaningful only in STDIO mode. In HTTP mode the database is expressed via the URL path (sub-task 2).

This change must land in the v2 branch and must not be backported to main.

[Andy2003]

@MacondoExpress Can I support on this Issue?

[MacondoExpress]

You eventually can,
However, we need some design around this issue. The primary concern that this design should address is whether this feature will be compatible in a multi-tenant environment.
So unfortunately, we're not yet clear on which direction take regarding this.

[MacondoExpress]

Sorry this was closed by mistake