MCP spec conformance (math-mcp example): 1 requirement violated (via @hasmcp/mcp-spec-test) — spec 2025-11-25

[hasmcp-dev]

When run through @hasmcp/mcp-spec-test (spec revision 2025-11-25), the bundled mcp_servers/math-mcp server fails 1 conformance requirement: the initialize handshake responds with the legacy protocol version 2024-11-05 even when a client offers 2025-11-25, rather than settling on a revision inside the currently-supported window. This is the same underlying cause (a hardcoded/outdated protocolVersion in the server's initialize response) as the larger set of failures reported for revision 2026-07-28 in the separate issue filed alongside this one.

Conformance report (spec 2025-11-25)

MCP 2025-11-25 conformance report

Verdict: not conformant — 1 requirement violated.

Target	sh -c '\[ -d /tmp/bench \] || git clone --depth 1 -q https://github.com/Accenture/mcp-bench /tmp/bench; cd /tmp/bench/mcp\_servers/math-mcp && \[ -d build \] || (npm install --silent \>/dev/null 2\>&1 && npm run build --silent \>/dev/null 2\>&1); node build/index.js'
Transport	stdio
Revision tested	2025-11-25
Revisions supported	2026-07-28, 2025-11-25
Passed	6
Failed	1
Not verified	13
Cases applied	20
Duration	1446ms
Generated	2026-08-24T04:56:03.069Z
Tool	@hasmcp/mcp-spec-test 0.1.1

Failed (1)

the server deviates from the spec here

Official SDK interop

• the handshake settles on a revision inside the supported window
  a client offering 2025-11-25 was answered with 2024-11-05, outside the supported window (2026-07-28, 2025-11-25)

Not verified (13)

skipped; a skip is not a pass

Capability methods

• tools/list returns schema-conformant tools
  cannot determine what the target supports — server negotiated 2024-11-05, not the 2025-11-25 under test
• tools/call on an unknown tool is an error, not a crash
  cannot determine what the target supports — server negotiated 2024-11-05, not the 2025-11-25 under test
• tools/call returns a schema-conformant CallToolResult
  cannot determine what the target supports — server negotiated 2024-11-05, not the 2025-11-25 under test
• prompts/list returns schema-conformant prompts
  cannot determine what the target supports — server negotiated 2024-11-05, not the 2025-11-25 under test
• prompts/get returns messages with a role and content
  cannot determine what the target supports — server negotiated 2024-11-05, not the 2025-11-25 under test
• resources/list returns schema-conformant resources
  cannot determine what the target supports — server negotiated 2024-11-05, not the 2025-11-25 under test
• resources/templates/list returns schema-conformant templates
  cannot determine what the target supports — server negotiated 2024-11-05, not the 2025-11-25 under test
• resources/read returns contents for every sampled resource
  cannot determine what the target supports — server negotiated 2024-11-05, not the 2025-11-25 under test
• resources/read on an unknown uri is an error
  cannot determine what the target supports — server negotiated 2024-11-05, not the 2025-11-25 under test
• following nextCursor terminates and does not repeat a page
  cannot determine what the target supports — server negotiated 2024-11-05, not the 2025-11-25 under test
• an invalid pagination cursor is rejected (SHOULD)
  cannot determine what the target supports — server negotiated 2024-11-05, not the 2025-11-25 under test

Version negotiation

• initialize returns the schema-required fields
  no session — server negotiated 2024-11-05, not the 2025-11-25 under test
• the handshake settles on the revision under test
  no session — server negotiated 2024-11-05, not the 2025-11-25 under test

Passed (6)

checked and conformant

server/discover

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

Version negotiation

• a request with no version at all is served on the default
• an unsupported version offered at the handshake is refused or downgraded, not echoed

Official SDK interop

• the official SDK does not yet implement the newest revision
• a stock official-SDK client completes the handshake
• a stock official-SDK client can list tools

How to reproduce

With Docker:

docker pull hasmcp/mcp-spec-test:latest
docker run --rm hasmcp/mcp-spec-test -c "sh -c '[ -d /tmp/bench ] || git clone --depth 1 -q https://github.com/Accenture/mcp-bench /tmp/bench; cd /tmp/bench/mcp_servers/math-mcp && [ -d build ] || (npm install --silent >/dev/null 2>&1 && npm run build --silent >/dev/null 2>&1); node build/index.js'" --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 "..." --spec-version 2025-11-25)

Without Docker (npx):

npx @hasmcp/mcp-spec-test@latest -c "sh -c '[ -d /tmp/bench ] || git clone --depth 1 -q https://github.com/Accenture/mcp-bench /tmp/bench; cd /tmp/bench/mcp_servers/math-mcp && [ -d build ] || (npm install --silent >/dev/null 2>&1 && npm run build --silent >/dev/null 2>&1); node build/index.js'" --spec-version 2025-11-25

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This was filed by an automated MCP spec-conformance sweep against the math-mcp example server bundled in this repo. The same server also fails 7 requirements against revision 2026-07-28, tracked in a separate issue (linked above/below).