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chore: renumber draft error codes per modelcontextprotocol#2907 (#353)

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The error-code allocation policy in modelcontextprotocol#2907 renumbers
the draft-only codes: HeaderMismatch -32001 -> -32020,
MissingRequiredClientCapability -32003 -> -32021,
UnsupportedProtocolVersion -32004 -> -32022. This updates every
reference in the suite (mocks, scenarios, fixtures, tests, traceability
yaml) and re-syncs the vendored draft schema to that commit.

src/seps/traceability.json is generated and intentionally left for the
scheduled refresh workflow.
This commit is contained in:
Felix Weinberger 2026-06-18 17:17:54 +01:00 • committed by GitHub
commit fe3a3103bc
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2 changed files with 73 additions and 57 deletions
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8
examples/clients/typescript/everything-client.ts
View file

@ -265,12 +265,8 @@ async function runRequestMetadataClient(serverUrl: string): Promise<void> {
const clone = response.clone();
try {
const errorResult = await clone.json();
// -32004 is UnsupportedProtocolVersionError in the draft schema;
// -32001 is tolerated for servers that predate the dedicated code.
if (
errorResult.error?.code === -32004 ||
errorResult.error?.code === -32001
) {
// UnsupportedProtocolVersionError is -32022 in the draft schema.
if (errorResult.error?.code === -32022) {
logger.debug(
'Received UnsupportedProtocolVersionError, starting negotiation...'
);

14
examples/servers/typescript/everything-server.ts
View file

@ -1260,7 +1260,7 @@ app.post('/mcp', async (req, res) => {
return res.status(400).json({
jsonrpc: '2.0',
id,
error: { code: -32001, message: 'Missing MCP-Protocol-Version header' }
error: { code: -32020, message: 'Missing MCP-Protocol-Version header' }
});
}
@ -1283,25 +1283,25 @@ app.post('/mcp', async (req, res) => {
});
}
// Header Mismatch Verification (-32001, HTTP 400)
// Header Mismatch Verification (-32020, HTTP 400)
if (reqVersion !== metaVersion) {
return res.status(400).json({
jsonrpc: '2.0',
id,
error: {
code: -32001,
code: -32020,
message: 'Mismatched MCP-Protocol-Version header'
}
});
}
// Protocol Version Negotiation Matrix (-32004, HTTP 400)
// Protocol Version Negotiation Matrix (-32022, HTTP 400)
if (metaVersion !== '2026-07-28') {
return res.status(400).json({
jsonrpc: '2.0',
id,
error: {
code: -32004,
code: -32022,
message: 'UnsupportedProtocolVersionError',
data: {
supported: ['2026-07-28'],
@ -1655,13 +1655,13 @@ app.post('/mcp', async (req, res) => {
if (name === 'test_missing_capability') {
const clientCaps = meta['io.modelcontextprotocol/clientCapabilities'];
// Missing Required Client Capability Check (-32003, HTTP 400)
// Missing Required Client Capability Check (-32021, HTTP 400)
if (!clientCaps?.sampling) {
return res.status(400).json({
jsonrpc: '2.0',
id,
error: {
code: -32003,
code: -32021,
message: 'MissingRequiredClientCapabilityError',
data: { requiredCapabilities: ['sampling'] }
}