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nmaguiar merged 2 commits into from
Mar 28, 2026
Merged

Expose MCP JSON-RPC protocol metadata via $mcp.getClientInfo #1792

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6c3d81b
Add MCP client protocol data to getClientInfo
nmaguiar Mar 28, 2026
9892665
Enhance MCP functionality by adding synthetic capabilities and server…
nmaguiar Mar 28, 2026
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96 changes: 90 additions & 6 deletions js/openaf.js
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -8503,6 +8503,13 @@ const $jsonrpc = function (aOptions) {
mcpSessionId: __
}

const _mcpInfo = {
session: _session,
lastRequest: __,
lastResponse: __,
lastResponseHeaders: __
}

const _captureSessionFromHeaders = headers => {
var _sid = _pickHeaderCaseInsensitive(headers, "mcp-session-id")
if (isDef(_sid) && String(_sid).length > 0) {
Expand Down Expand Up @@ -8680,6 +8687,11 @@ const $jsonrpc = function (aOptions) {
},
exec: (aMethod, aParams, aNotification, aExecOptions) => {
aExecOptions = _$(aExecOptions, "aExecOptions").isMap().default({})
_mcpInfo.lastRequest = {
method: _$(aMethod, "aMethod").isString().default(__),
params: _$(aParams, "aParams").isMap().default({}),
notification: !!aNotification
}
switch (aOptions.type) {
case "dummy":
aOptions.options = _$(aOptions.options, "aOptions.options").isMap().default({})
Expand All @@ -8690,11 +8702,15 @@ const $jsonrpc = function (aOptions) {
if (isMap(aOptions.options.fns)) {
if (isFunction(aOptions.options.fns[aMethod])) {
var _res = aOptions.options.fns[aMethod](aParams)
_debug("jsonrpc dummy <- " + stringify({ result: _res }, __, ""))
_mcpInfo.lastResponse = { jsonrpc: "2.0", result: _res }
_mcpInfo.lastResponseHeaders = __
_debug("jsonrpc dummy <- " + stringify(_mcpInfo.lastResponse, __, ""))
if (aMethod == "initialize" && !aNotification) _r._info = _res
return _res
} else {
_debug("jsonrpc dummy <- " + stringify({ error: "Method not found" }, __, ""))
_mcpInfo.lastResponse = { jsonrpc: "2.0", error: { code: -32601, message: "Method not found" } }
_mcpInfo.lastResponseHeaders = __
_debug("jsonrpc dummy <- " + stringify(_mcpInfo.lastResponse, __, ""))
throw new Error("Method not found")
}
}
Expand Down Expand Up @@ -8730,6 +8746,8 @@ const $jsonrpc = function (aOptions) {
_res = _r._r[_id]
delete _r._r[_id]
}
_mcpInfo.lastResponse = _res
_mcpInfo.lastResponseHeaders = __
if (aMethod == "initialize" && !aNotification) _r._info = isDef(_res) && isDef(_res.result) ? _res.result : _res
return isDef(_res) && isDef(_res.result) ? _res.result : _res
case "sse":
Expand Down Expand Up @@ -8774,13 +8792,16 @@ const $jsonrpc = function (aOptions) {
if (!!aNotification) {
var _notificationRes = $rest(_restOptions).post2Stream(aOptions.url, _req)
_captureSessionFromHeaders(_http.responseHeaders())
_mcpInfo.lastResponseHeaders = clone(_http.responseHeaders())
_mcpInfo.lastResponse = __
if (isDef(_notificationRes) && "function" === typeof _notificationRes.close) {
try { _notificationRes.close() } catch(e) {}
}
return
}
var _streamRes = $rest(_restOptions).post2Stream(aOptions.url, _req)
_captureSessionFromHeaders(_http.responseHeaders())
_mcpInfo.lastResponseHeaders = clone(_http.responseHeaders())
var _events = _r._readSSE(_streamRes)
res = _events.filter(r => isMap(r)).filter(r => r.id == _req.id || isUnDef(r.id)).shift()
if (isUnDef(res) && _events.length > 0) res = _events[0]
Expand All @@ -8789,7 +8810,9 @@ const $jsonrpc = function (aOptions) {
_restOptions.httpClient = _http
res = $rest(_restOptions).post(aOptions.url, _req)
_captureSessionFromHeaders(_http.responseHeaders())
_mcpInfo.lastResponseHeaders = clone(_http.responseHeaders())
}
_mcpInfo.lastResponse = res
// Notifications do not expect a reply
if (!!aNotification) return
_debug("jsonrpc <- " + stringify(res, __, ""))
Expand All @@ -8802,6 +8825,7 @@ const $jsonrpc = function (aOptions) {
}
},
getInfo: () => _r._info,
getClientInfo: () => merge({}, _mcpInfo),
destroy: () => {
if (_r._copies.get() > 0) {
_r._copies.dec()
Expand Down Expand Up @@ -9005,6 +9029,31 @@ const $mcp = function(aOptions) {
_toolBlacklist[toolName] = true
})

const _buildSyntheticCapabilities = fns => {
var _caps = {}
fns = _$(fns, "fns").isMap().default({})
var _fnNames = Object.keys(fns)
var _hasCustomTools = _fnNames.some(name => ["tools/list", "tools/call", "initialize", "notifications/initialized"].indexOf(name) < 0)
if (_hasCustomTools || isDef(fns["tools/list"]) || isDef(fns["tools/call"])) _caps.tools = { listChanged: false }
if (isDef(fns["prompts/list"]) || isDef(fns["prompts/get"])) _caps.prompts = { listChanged: false }
if (isDef(fns["resources/list"]) || isDef(fns["resources/read"]) || isDef(fns["resources/templates/list"])) _caps.resources = { listChanged: false }
if (isDef(fns["logging/setLevel"])) _caps.logging = {}
if (isDef(fns["agents/list"]) || isDef(fns["agents/get"]) || isDef(fns["agents/send"])) _caps.agents = {}
return _caps
}

const _buildSyntheticInitializeResult = opts => {
opts = _$(opts, "opts").isMap().default({})
var _result = {
protocolVersion: _$(opts.protocolVersion, "opts.protocolVersion").isString().default(aOptions.protocolVersion)
}
var _serverInfo = _$(opts.serverInfo, "opts.serverInfo").isMap().default(__)
var _capabilities = _$(opts.capabilities, "opts.capabilities").isMap().default(__)
if (isMap(_serverInfo)) _result.serverInfo = clone(_serverInfo)
if (isMap(_capabilities)) _result.capabilities = clone(_capabilities)
return _result
}

const _defaultCmdDir = (isDef(__flags) && isDef(__flags.JSONRPC) && isDef(__flags.JSONRPC.cmd) && isDef(__flags.JSONRPC.cmd.defaultDir)) ? __flags.JSONRPC.cmd.defaultDir : __
const _isToolBlacklisted = toolName => _toolBlacklist[toolName] === true
const _filterToolsList = toolsRes => {
Expand Down Expand Up @@ -9261,7 +9310,7 @@ const $mcp = function(aOptions) {
aOptions.options.init = _$(aOptions.options.init, "aOptions.options.init").default(__)

// Load jobs from the oJob
var fnsMeta = {}, fns = {}
var fnsMeta = {}, fns = {}, _initMeta = {}
var jobsTemp = io.createTempFile("ojob_mcp_", ".yaml")
var jobsPreD = aOptions.options.job.endsWith(".json") ? io.readFileJSON(_defaultCmdDir + String(java.io.File.separator) + aOptions.options.job) : io.readFileYAML(_defaultCmdDir + String(java.io.File.separator) + aOptions.options.job)
if (isDef(jobsPreD.ojob) && isDef(jobsPreD.ojob.daemon)) delete jobsPreD.ojob.daemon
Expand Down Expand Up @@ -9318,8 +9367,30 @@ const $mcp = function(aOptions) {
throw new Error("Invalid oJob data loaded from " + aOptions.options.job)
}

var _serverInfoEntries = searchKeys(jobsPreD, "serverInfo")
if (isMap(_serverInfoEntries)) {
var _serverInfoKey = Object.keys(_serverInfoEntries).find(k => isMap(_serverInfoEntries[k]))
if (isDef(_serverInfoKey)) _initMeta.serverInfo = clone(_serverInfoEntries[_serverInfoKey])
}
var _capabilitiesEntries = searchKeys(jobsPreD, "capabilities")
if (isMap(_capabilitiesEntries)) {
var _capabilitiesKey = Object.keys(_capabilitiesEntries).find(k => isMap(_capabilitiesEntries[k]))
if (isDef(_capabilitiesKey)) _initMeta.capabilities = clone(_capabilitiesEntries[_capabilitiesKey])
}
var _protocolVersionEntries = searchKeys(jobsPreD, "protocolVersion")
if (isMap(_protocolVersionEntries)) {
var _protocolVersionKey = Object.keys(_protocolVersionEntries).find(k => isString(_protocolVersionEntries[k]))
if (isDef(_protocolVersionKey)) _initMeta.protocolVersion = String(_protocolVersionEntries[_protocolVersionKey])
}

aOptions.type = "dummy"
aOptions.options.fnsMeta = fnsMeta
aOptions.options.serverInfo = _$(aOptions.options.serverInfo, "aOptions.options.serverInfo").isMap().default(_$( _initMeta.serverInfo, "_initMeta.serverInfo").isMap().default({
name: "OpenAF oJob MCP",
version: "1.0.0"
}))
aOptions.options.capabilities = _$(aOptions.options.capabilities, "aOptions.options.capabilities").isMap().default(_$( _initMeta.capabilities, "_initMeta.capabilities").isMap().default(_buildSyntheticCapabilities(fns)))
aOptions.options.protocolVersion = _$(aOptions.options.protocolVersion, "aOptions.options.protocolVersion").isString().default(_$( _initMeta.protocolVersion, "_initMeta.protocolVersion").isString().default(aOptions.protocolVersion))
aOptions.options.fns["tools/list"] = params => {
return {
tools: Object.keys(fns)
Expand All @@ -9333,7 +9404,7 @@ const $mcp = function(aOptions) {
return $job(fns[params.name], params.arguments)
}
aOptions.options.fns["initialize"] = params => {
return { protocolVersion: "2024-11-05" }
return _buildSyntheticInitializeResult(aOptions.options)
}
aOptions.options.fns["notifications/initialized"] = params => {
return {}
Expand All @@ -9342,6 +9413,12 @@ const $mcp = function(aOptions) {
aOptions.options = _$(aOptions.options, "aOptions.options").isMap().default({})
aOptions.options.fns = _$(aOptions.options.fns, "aOptions.options.fns").isMap().default({})
aOptions.options.fnsMeta = _$(aOptions.options.fnsMeta, "aOptions.options.fnsMeta").isMap().default({})
aOptions.options.serverInfo = _$(aOptions.options.serverInfo, "aOptions.options.serverInfo").isMap().default({
name: "OpenAF Dummy MCP",
version: "1.0.0"
})
aOptions.options.capabilities = _$(aOptions.options.capabilities, "aOptions.options.capabilities").isMap().default(_buildSyntheticCapabilities(aOptions.options.fns))
aOptions.options.protocolVersion = _$(aOptions.options.protocolVersion, "aOptions.options.protocolVersion").isString().default(aOptions.protocolVersion)

aOptions.options.fns["tools/list"] = params => {
return {
Expand All @@ -9356,7 +9433,7 @@ const $mcp = function(aOptions) {
return aOptions.options.fns[params.name](params.arguments)
}
aOptions.options.fns["initialize"] = params => {
return { protocolVersion: "2024-11-05" }
return _buildSyntheticInitializeResult(aOptions.options)
}
aOptions.options.fns["notifications/initialized"] = params => {
return {}
Expand Down Expand Up @@ -9448,6 +9525,13 @@ const $mcp = function(aOptions) {
}
},
getInfo: () => _r._initResult,
getClientInfo: () => {
var _clientInfo = _jsonrpc.getClientInfo()
if (isMap(_r._initResult)) {
_clientInfo.initialize = clone(_r._initResult)
}
return _clientInfo
},
listTools: () => {
if (!_r._initialized) {
throw new Error("MCP client not initialized. Call initialize() first.")
Expand Down Expand Up @@ -9503,7 +9587,7 @@ const $mcp = function(aOptions) {
* <key>$mcp.listAgents() : Map</key>
* Lists all available A2A agents from the MCP server.\
* Returns a map with an 'agents' array containing agent metadata (id, name, title, version, tags, capabilities).\
* Must call initialize() first.\
return _buildSyntheticInitializeResult(aOptions.options)
* \
* Example:\
* \
Expand Down
36 changes: 35 additions & 1 deletion tests/autoTestAll.MCP.js
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -84,11 +84,14 @@

if (isNotification) return ow.server.httpd.reply("", 204, "text/plain", {});

var responseHeaders = {};
if (rpc.method == "initialize") responseHeaders["mcp-session-id"] = "test-session-1";

return ow.server.httpd.reply({
jsonrpc: "2.0",
result: result,
id: rpc.id
}, 200, "application/json", {});
}, 200, "application/json", responseHeaders);
}
});

Expand Down Expand Up @@ -199,4 +202,35 @@
}
});
};

exports.testGetClientInfoIncludesJSONRPCMCPData = function() {
withOAuthMCPServer(function(ctx) {
var client = $mcp({
type: "remote",
strict: false,
url: ctx.resource,
auth: {
type: "oauth2",
grantType: "client_credentials",
clientId: "client-a",
clientSecret: "secret-a"
}
});

try {
client.initialize({ name: "TestClient", version: "9.9.9" });
var info = client.getClientInfo();

ow.test.assert(info.lastRequest.method, "initialize", "getClientInfo should include the last JSON-RPC method.");
ow.test.assert(info.lastRequest.params.protocolVersion, "2024-11-05", "getClientInfo should include initialize protocolVersion.");
ow.test.assert(info.lastRequest.params.clientInfo.name, "TestClient", "getClientInfo should include sent clientInfo.");
ow.test.assert(info.lastResponse.jsonrpc, "2.0", "getClientInfo should include raw JSON-RPC response envelope.");
ow.test.assert(info.lastResponse.result.serverInfo.name, "OAuth MCP", "getClientInfo should include JSON-RPC result data.");
ow.test.assert(info.session.mcpSessionId, "test-session-1", "getClientInfo should include captured MCP session id.");
ow.test.assert(info.initialize.protocolVersion, "2024-11-05", "getClientInfo should include initialize result data.");
} finally {
client.destroy();
}
});
};
})();
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