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

[hasmcp-dev]

Running @hasmcp/mcp-spec-test against the examples/dice-roller server on MCP spec revision 2025-11-25, the server process exits without responding to any request. As detailed in the companion issue for the newer 2026-07-28 revision: requirements.txt pins only mcp[cli]>=1.2.0 with no ceiling, so a fresh install grabs the newest mcp package (currently v2.1.0), which no longer exposes mcp.server.fastmcp — dice_server.py's from mcp.server.fastmcp import FastMCP fails with ModuleNotFoundError before the server can bind stdio.

Conformance report

MCP 2025-11-25 conformance report

Verdict: not conformant — 5 requirements violated.

Target	sh -c '[ -d /tmp/dice ] || git clone --depth 1 https://github.com/theNetworkChuck/docker-mcp-tutorial /tmp/dice; cd /tmp/dice/examples/dice-roller && pip install --break-system-packages -q -r requirements.txt && python3 dice_server.py'
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	9110ms
Generated	2026-08-24T19:14:27.990Z
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 "sh -c '[ -d /tmp/dice ] || git clone --depth 1 https://github.com/theNetworkChuck/docker-mcp-tutorial /tmp/dice; cd /tmp/dice/examples/dice-roller && pip install --break-system-packages -r requirements.txt && python3 dice_server.py'" --spec-version 2025-11-25

(or, if that image can't run on your platform: git clone https://github.com/hasmcp/mcp-spec-test && cd mcp-spec-test && docker build -t mcp-spec-test . && docker run --rm mcp-spec-test -c "sh -c '[ -d /tmp/dice ] || git clone --depth 1 https://github.com/theNetworkChuck/docker-mcp-tutorial /tmp/dice; cd /tmp/dice/examples/dice-roller && pip install --break-system-packages -r requirements.txt && python3 dice_server.py'" --spec-version 2025-11-25)

Without Docker (npx):

npx @hasmcp/mcp-spec-test@latest -c "sh -c '[ -d /tmp/dice ] || git clone --depth 1 https://github.com/theNetworkChuck/docker-mcp-tutorial /tmp/dice; cd /tmp/dice/examples/dice-roller && pip install --break-system-packages -r requirements.txt && python3 dice_server.py'" --spec-version 2025-11-25

This was generated by an automated conformance sweep. See also #15, the companion issue for the same repo against the newer 2026-07-28 revision (10 violations there vs 5 here — same root cause). The maintainer is welcome to close this if it's not applicable.