MCP spec conformance: 5 requirements violated (via @hasmcp/mcp-spec-test) — spec 2025-11-25

Comienza con examples/qr-server/server.py y reproduce el comando informado utilizando las instrucciones de Docker o npx con la spec version 2025-11-25. Comprueba si el proceso termina antes del MCP handshake y determina si se trata de un problema real del servidor o de un artefacto del entorno, la red o el script remoto de uv. Se considera terminado cuando el servidor completa el handshake y los fallos de conformance se han corregido o confirmado como falsos positivos.

Running the automated @hasmcp/mcp-spec-test conformance suite against the examples/qr-server/server.py stdio server, this time pinned to spec revision 2025-11-25, found the same underlying issue as with the newer revision: the server process exits before completing the MCP handshake. Under this revision that surfaces as 5 failed requirements (versus 10 under 2026-07-28), since fewer handshake-dependent cases apply at this revision. As with the other report, this may be an environment/dependency artifact of running uv run against a remote script URL inside the test container rather than a genuine server bug — flagging for a maintainer to confirm.

Conformance report

MCP 2025-11-25 conformance report

Verdict: not conformant — 5 requirements violated.

Target	uv run https://raw.githubusercontent.com/modelcontextprotocol/ext-apps/HEAD/examples/qr-server/server.py --stdio
Transport	stdio
Revision tested	2025-11-25
Revisions supported	2026-07-28, 2025-11-25
Passed	2
Failed	5
Not verified	13
Cases applied	20
Duration	10394ms
Generated	2026-08-24T09:21:52.168Z
Tool	@hasmcp/mcp-spec-test 0.1.1

Failed (5)

the server deviates from the spec here

Version negotiation

• a request with no version at all is served on the default
  a version-less request must be served, got 0: {"_raw":"server exited"}

0 !== 200

• an unsupported version offered at the handshake is refused or downgraded, not echoed
  expected either an error or a protocolVersion, got {"_raw":"server exited"}

Official SDK interop

• a stock official-SDK client completes the handshake
  MCP error -32000: Connection closed
• the handshake settles on a revision inside the supported window
  initialize must return a protocolVersion, got undefined
• a stock official-SDK client can list tools
  MCP error -32000: Connection closed

Not verified (13)

skipped; a skip is not a pass

Capability methods

• tools/list returns schema-conformant tools
  cannot determine what the target supports — initialize returned no result (status 0)
• tools/call on an unknown tool is an error, not a crash
  cannot determine what the target supports — initialize returned no result (status 0)
• tools/call returns a schema-conformant CallToolResult
  cannot determine what the target supports — initialize returned no result (status 0)
• prompts/list returns schema-conformant prompts
  cannot determine what the target supports — initialize returned no result (status 0)
• prompts/get returns messages with a role and content
  cannot determine what the target supports — initialize returned no result (status 0)
• resources/list returns schema-conformant resources
  cannot determine what the target supports — initialize returned no result (status 0)
• resources/templates/list returns schema-conformant templates
  cannot determine what the target supports — initialize returned no result (status 0)
• resources/read returns contents for every sampled resource
  cannot determine what the target supports — initialize returned no result (status 0)
• resources/read on an unknown uri is an error
  cannot determine what the target supports — initialize returned no result (status 0)
• following nextCursor terminates and does not repeat a page
  cannot determine what the target supports — initialize returned no result (status 0)
• an invalid pagination cursor is rejected (SHOULD)
  cannot determine what the target supports — initialize returned no result (status 0)

Version negotiation

• initialize returns the schema-required fields
  no session — initialize returned no result (status 0)
• the handshake settles on the revision under test
  no session — initialize returned no result (status 0)

Passed (2)

checked and conformant

server/discover

• the suite is reading a schema that matches the features it selected

Official SDK interop

• the official SDK does not yet implement the newest revision

How to reproduce

With Docker:

docker pull hasmcp/mcp-spec-test:latest
docker run --rm hasmcp/mcp-spec-test -c "uv run https://raw.githubusercontent.com/modelcontextprotocol/ext-apps/HEAD/examples/qr-server/server.py --stdio" --spec-version 2025-11-25

Without Docker (npx):

npx @hasmcp/mcp-spec-test@latest -c "uv run https://raw.githubusercontent.com/modelcontextprotocol/ext-apps/HEAD/examples/qr-server/server.py --stdio" --spec-version 2025-11-25

This report was generated as part of an automated conformance sweep across public MCP server repos. The server also supports spec revision 2026-07-28, which showed a different (larger) set of failures and is reported separately. If this turns out to be a false positive specific to the test container's environment (e.g. missing uv/network access to fetch the remote script, or a uv run <url> invocation quirk rather than a real handshake bug), feel free to close this — happy to help re-verify with more detail if useful.